id
stringlengths 9
16
| submitter
stringlengths 1
64
⌀ | authors
stringlengths 3
62.8k
| title
stringlengths 1
382
| comments
stringlengths 1
1.15k
⌀ | journal-ref
stringlengths 1
557
⌀ | doi
stringlengths 7
153
⌀ | report-no
stringlengths 1
509
⌀ | categories
stringlengths 5
125
| license
stringclasses 9
values | abstract
stringlengths 6
6.09k
| versions
listlengths 1
187
| update_date
timestamp[s]date 2007-05-23 00:00:00
2025-04-04 00:00:00
| authors_parsed
sequencelengths 1
2.83k
|
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
quant-ph/9905043 | Alexandre M. Zagoskin | Alexandre Blais and Alexandre M. Zagoskin | Operation of universal gates in a DXD superconducting solid state
quantum computer | 4 pages, 2 figures | Physical Review A, v.61, 042308 (2000) | 10.1103/PhysRevA.61.042308 | null | quant-ph cond-mat.mes-hall cond-mat.other cond-mat.supr-con cs.GL | null | We demonstrate that complete set of gates can be realized in a DXD
superconducting solid state quantum computer (quamputer), thereby proving its
universality.
| [
{
"version": "v1",
"created": "Thu, 13 May 1999 21:44:55 GMT"
},
{
"version": "v2",
"created": "Fri, 7 Apr 2000 23:42:37 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Blais",
"Alexandre",
""
],
[
"Zagoskin",
"Alexandre M.",
""
]
] |
quant-ph/9905044 | Jun Yan | Guang-jiong Ni, Weimin Zhou and Jun Yan | Klein paradox and antiparticle | 4 pages, no figures, revtex | null | null | null | quant-ph | null | The Klein paradox of Klein-Gordon (KG) equation is discussed to show that KG
equation is self-consistent even at one-particle level and the wave function
for antiparticle is uniquely determined by the reasonable explanation of Klein
paradox. No concept of ``hole'' is needed.
| [
{
"version": "v1",
"created": "Thu, 13 May 1999 20:57:53 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Ni",
"Guang-jiong",
""
],
[
"Zhou",
"Weimin",
""
],
[
"Yan",
"Jun",
""
]
] |
quant-ph/9905045 | Timothy F. Havel | S. S. Somaroo, C. H. Tseng, T. F. Havel, R. Laflamme, D. G. Cory | Quantum Simulations on a Quantum Computer | 4 pages, 2 figures (\documentstyle[prl,aps,epsfig,amscd]{revtex}); to
appear in Phys. Rev. Lett | Phys.Rev.Lett.82:5381-5384,1999 | 10.1103/PhysRevLett.82.5381 | null | quant-ph | null | We present a general scheme for performing a simulation of the dynamics of
one quantum system using another. This scheme is used to experimentally
simulate the dynamics of truncated quantum harmonic and anharmonic oscillators
using nuclear magnetic resonance. We believe this to be the first explicit
physical realization of such a simulation.
| [
{
"version": "v1",
"created": "Thu, 13 May 1999 22:29:09 GMT"
}
] | 2009-01-23T00:00:00 | [
[
"Somaroo",
"S. S.",
""
],
[
"Tseng",
"C. H.",
""
],
[
"Havel",
"T. F.",
""
],
[
"Laflamme",
"R.",
""
],
[
"Cory",
"D. G.",
""
]
] |
quant-ph/9905046 | Waldemar Puszkarz | Waldemar Puszkarz | Non-separability without Non-separability in Nonlinear Quantum Mechanics | Latex, 13 pages | null | null | null | quant-ph | null | We show an example of benign non-separability in an apparently separable
system consisting of $n$ free non-correlated quantum particles, solitonic
solutions to the nonlinear phase modification of the Schr\"{o}dinger equation
proposed recently. The non-separability manifests itself in the wave function
of a single particle being influenced by the very presence of other particles.
In the simplest case of identical particles, it is the number of particles that
affects the wave function of each particle and, in particular, the width of its
Gaussian probability density. As a result, this width, a local property, is
directly linked to the mass of the entire Universe in a very Machian manner. In
the realistic limit of large $n$ if the width in question is to be microscopic,
the coupling constant must be very small resulting in an ``almost linear''
theory. This provides a model explanation of why the linearity of quantum
mechanics can be accepted with such a high degree of certainty even if the more
fundamental underlying theory could be nonlinear. We also demonstrate that when
such non-correlated solitons are coupled to harmonic oscilators they lead to a
faster-than-light nonlocal telegraph since changing the frequency of one
oscillator affects instantaneously the probability density of particles
associated with other oscillators. This effect can be alleviated by fine-tuning
the parameters of the solution. Exclusion rules of a novel kind that we term
supersuperselection rules also emerge from these solutions. They are similar to
the mass and the univalence superselection rules in linear quantum mechanics.
The effects in question and the exclusion rules do not appear if a weakly
separable extension to $n$-particles is employed.
| [
{
"version": "v1",
"created": "Fri, 14 May 1999 08:15:27 GMT"
},
{
"version": "v2",
"created": "Mon, 17 May 1999 03:28:00 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Puszkarz",
"Waldemar",
""
]
] |
quant-ph/9905047 | Laboratory of nanophysics | Yu. Lozovik, A. Filinov | Transmission time of wave packets through tunneling barriers | 23 pages, 5 figures | J.Exp.Theor.Phys. 88 (1999) 1026-1035; Zh.Eksp.Teor.Fiz. 115
(1999) 1872-1889 | 10.1134/1.558886 | ISAN-99-20 | quant-ph | null | The transmission of wave packets through tunneling barriers is studied in
detail by the method of quantum molecular dynamics. The distribution function
of the times describing the arrival of a tunneling packet in front of and
behind a barrier and the momentum distribution function of the packet are
calculated. The behavior of the average coordinate of a packet, the average
momentum, and their variances is investigated. It is found that under the
barrier a part of the packet is reflected and a Gaussian barrier increases the
average momentum of the transmitted packet and its variance in momentum space.
| [
{
"version": "v1",
"created": "Fri, 14 May 1999 10:28:05 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Lozovik",
"Yu.",
""
],
[
"Filinov",
"A.",
""
]
] |
quant-ph/9905048 | DE MARTINI Francesco | F.A. Bovino, F. De Martini, V. Mussi | Quantum Superposition of Parametrically Amplified Multiphoton Pure
States whitin a Decoherence-Free Schroedinger-Cat Structure | 25 pages, 5 figures, submitted to Phys. Rev. A | null | null | null | quant-ph | null | The new process of quantum-injection into an optical parametric amplifier
operating in entangled configuration is adopted to amplify into a large
dimensionality spin 1/2 Hilbert space the quantum entanglement and
superposition properties of the photon-couples generated by parametric
down-conversion. The structure of the Wigner function and of the field's
correlation functions shows a decoherence-free, multiphoton Schroedinger-cat
behaviour of the emitted field which is largely detectable against the
squeezed-vacuum noise. Furthermore, owing to its entanglement character, the
system is found to exhibit multi-particle quantum nonseparability and Bell-type
nonlocality properties. These relevant quantum features are analyzed for
several travelling-wave optical configurations implying different input
quantum-injection schemes
| [
{
"version": "v1",
"created": "Fri, 14 May 1999 11:52:51 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bovino",
"F. A.",
""
],
[
"De Martini",
"F.",
""
],
[
"Mussi",
"V.",
""
]
] |
quant-ph/9905049 | Gabriel Drobny | B. Hladky, G. Drobny (Institute of Physics, Bratislava), V. Buzek | Quantum synthesis of arbitrary unitary operators | 6 RevTeX pages with 3 figures, submitted to Phys.Rev.A, see also
http://nic.savba.sk/sav/inst/fyzi/qo/ | null | 10.1103/PhysRevA.61.022102 | null | quant-ph | null | Nature provides us with a restricted set of microscopic interactions. The
question is whether we can synthesize out of these fundamental interactions an
arbitrary unitary operator. In this paper we present a constructive algorithm
for realization of any unitary operator which acts on a (truncated) Hilbert
space of a single bosonic mode. In particular, we consider a physical
implementation of unitary transformations acting on 1-dimensional vibrational
states of a trapped ion. As an example we present an algorithm which realizes
the discrete Fourier transform.
| [
{
"version": "v1",
"created": "Fri, 14 May 1999 16:54:02 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Hladky",
"B.",
"",
"Institute of Physics, Bratislava"
],
[
"Drobny",
"G.",
"",
"Institute of Physics, Bratislava"
],
[
"Buzek",
"V.",
""
]
] |
quant-ph/9905050 | Steve Simon | Steven H. Simon and P. M. Platzman (Bell Labs) | Fundamental Limit on ``Interaction Free'' Measurements | null | null | 10.1103/PhysRevA.61.052103 | BL-SHS-99005 | quant-ph | null | In ``interaction free'' measurements, one typically wants to detect the
presence of an object without touching it with even a single photon. One often
imagines a bomb whose trigger is an extremely sensitive measuring device whose
presence we would like to detect without triggering it. We point out that all
such measuring devices have a maximum sensitivity set by the uncertainty
principle, and thus can only determine whether a measurement is ``interaction
free'' to within a finite minimum resolution. We further discuss exactly what
can be achieved with the proposed ``interaction free'' measurement schemes.
| [
{
"version": "v1",
"created": "Fri, 14 May 1999 19:52:14 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Simon",
"Steven H.",
"",
"Bell Labs"
],
[
"Platzman",
"P. M.",
"",
"Bell Labs"
]
] |
quant-ph/9905051 | Kendra Vant | G Ball, K Vant and N Christensen | A Numerical Investigation of the Effects of Classical Phase Space
Structure on a Quantum System | 15 pages, 22 figures | Phys.Rev.E61:1299-1311,2000 | 10.1103/PhysRevE.61.1299 | null | quant-ph | null | We present a detailed numerical study of a chaotic classical system and its
quantum counterpart. The system is a special case of a kicked rotor and for
certain parameter values possesses cantori dividing chaotic regions of the
classical phase space. We investigate the diffusion of particles through a
cantorus; classical diffusion is observed but quantum diffusion is only
significant when the classical phase space area escaping through the cantorus
per kicking period greatly exceeds Planck's constant. A quantum analysis
confirms that the cantori act as barriers. We numerically estimate the
classical phase space flux through the cantorus per kick and relate this
quantity to the behaviour of the quantum system. We introduce decoherence via
environmental interactions with the quantum system and observe the subsequent
increase in the transport of quantum particles through the boundary.
| [
{
"version": "v1",
"created": "Mon, 17 May 1999 01:48:11 GMT"
}
] | 2008-12-18T00:00:00 | [
[
"Ball",
"G",
""
],
[
"Vant",
"K",
""
],
[
"Christensen",
"N",
""
]
] |
quant-ph/9905052 | DE MARTINI Francesco | E. De Angelis, F. De Martini and P. Mataloni | Bose-Einstein Partition Statistics of Photons Emitted from a
Superradiant Active Microcavity | 9 pages, 3 figures, submitted to Phys. Rev. Lett | null | null | null | quant-ph | null | We report the results of the first investigation on the superradiant temporal
and spatial quantum dynamics of two dipoles excited in a planar symmetrical
microcavity by a controlled femtosecond two-pulse excitation. A superradiant
enhancement of the time decay of the dipole excitation for a decreasing
inter-dipole transverse distance R has been found. Furthermore, the photon
partition statistics of the emitted field is found to exhibit a striking
quantum behaviour for R<lc, the transverse extension of the single allowed
microcavity mode.
| [
{
"version": "v1",
"created": "Mon, 17 May 1999 13:29:20 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"De Angelis",
"E.",
""
],
[
"De Martini",
"F.",
""
],
[
"Mataloni",
"P.",
""
]
] |
quant-ph/9905053 | Henry Stapp | Henry P. Stapp | Quantum Ontologies and Mind-Matter Synthesis | 69 pages. Invited contribution to Xth Max Born Symposium: "Quantum
Future". Published in "Quantum Future", eds. P. Blanchard and A. Jadczyk,
Springer-Verlag, 1999, ISBN 3-540-65218-3. LBNL 40722 | null | 10.1007/BFb0105346 | null | quant-ph | null | Aspects of a quantum mechanical theory of a world containing efficacious
mental aspects that are closely tied to brains, but that are not identical to
brains.
| [
{
"version": "v1",
"created": "Mon, 17 May 1999 20:07:09 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Stapp",
"Henry P.",
""
]
] |
quant-ph/9905054 | Henry Stapp | Henry P. Stapp | Attention, Intention, and Will in Quantum Physics | Invited contribution to the Volition Issue of J. Conscious Studies,
July 1999. LBNL-42650 | null | null | null | quant-ph | null | The need for a self-observing quantum system to pose questions leads to a
tripartite quantum process involving a Schroedinger process that is local
deterministic, a Heisenberg process that poses the question, and a Dirac
process that picks the answer. In the classical limit where Planck's constant
is set to zero these three processes reduce to one single deterministic
classical process: the fine structure wherein lies the effect of mind upon
matter is obliterated.
| [
{
"version": "v1",
"created": "Mon, 17 May 1999 20:25:12 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Stapp",
"Henry P.",
""
]
] |
quant-ph/9905055 | Henry Stapp | Henry P. Stapp | Nonlocality, Counterfactual, and Consistent Histories | Version submitted today to Physical Review A. The Conclusions section
is shortened to a brief description of the conclusion: The paper develops a
version of modal logic that stays completely within the framework provided by
quantum principles, and then proves, within the framework of quantum
thinking, and in particular without invoking "hidden variables", a Bell-type
nonlocality result | null | null | null | quant-ph | null | The paper develops a version of modal logic that stays completely within the
framework provided by quantum principles, and then proves, within the framework
of quantum thinking, and in particular without invoking "hidden variables", a
Bell-type nonlocality result.
| [
{
"version": "v1",
"created": "Mon, 17 May 1999 20:39:17 GMT"
},
{
"version": "v2",
"created": "Tue, 8 Jun 1999 21:22:14 GMT"
},
{
"version": "v3",
"created": "Tue, 15 Jun 1999 17:16:13 GMT"
},
{
"version": "v4",
"created": "Mon, 16 Aug 1999 02:25:51 GMT"
},
{
"version": "v5",
"created": "Fri, 18 Feb 2000 19:23:32 GMT"
},
{
"version": "v6",
"created": "Tue, 27 Jun 2000 21:32:52 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Stapp",
"Henry P.",
""
]
] |
quant-ph/9905056 | Gregoire Ribordy | Gregoire Ribordy, Jean-Daniel Gautier, Nicolas Gisin, Olivier
Guinnard, Hugo Zbinden | Fast and User-friendly Quantum Key Distribution | 21 pages, 6 figures, added reference | null | 10.1080/09500340008244057 | null | quant-ph | null | Some guidelines for the comparison of different quantum key distribution
experiments are proposed. An improved 'plug & play' interferometric system
allowing fast key exchange is then introduced. Self-alignment and compensation
of birefringence remain. Original electronics implementing the BB84 protocol
and allowing user-friendly operation is presented. Key creation with 0.1 photon
per pulse at a rate of 486 Hz with a 5.4% QBER - corresponding to a net rate of
210Hz - over a 23 Km installed cable was performed.
| [
{
"version": "v1",
"created": "Tue, 18 May 1999 15:08:11 GMT"
},
{
"version": "v2",
"created": "Fri, 30 Jul 1999 13:26:56 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Ribordy",
"Gregoire",
""
],
[
"Gautier",
"Jean-Daniel",
""
],
[
"Gisin",
"Nicolas",
""
],
[
"Guinnard",
"Olivier",
""
],
[
"Zbinden",
"Hugo",
""
]
] |
quant-ph/9905057 | Konstantin B. Korotchenko | K.B. Korotchenko | The test particle motion equations metrical form in a potential field | 4 pages | Sov.Phys.J. 12 (1983) 55-58 | null | null | quant-ph hep-th math-ph math.MP | null | It is shown in the present work that the three-dimensional trajectories of an
electrical test particle in potential fields may be regarded as geodesic lines
lying on isotropic surfaces of some four-dimensional configurational space, the
connection of which has tortion, while the transference is nonmetric.
| [
{
"version": "v1",
"created": "Wed, 19 May 1999 08:33:57 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Korotchenko",
"K. B.",
""
]
] |
quant-ph/9905058 | Michal Horodecki | Michal Horodecki | Optimal compression for mixed signal states | RevTeX, 5 pages, improvement of the proof (changes in the formula
(16)) | Phys. Rev. A, 61, 052309 (2000) | 10.1103/PhysRevA.61.052309 | null | quant-ph | null | We consider the problem of the optimal compression rate in the case of the
source producing mixed signal states within the {\it visible} scheme (where
Alice, who is to compress the signal, can know the identities of the produced
states). We show that a simple strategy based on replacing the signal states
with their {\it extensions} gives {\it optimal} compression. As a result we
obtain a considerable simplification of the formula for optimal compression
rate within visible scheme.
| [
{
"version": "v1",
"created": "Wed, 19 May 1999 13:46:35 GMT"
},
{
"version": "v2",
"created": "Tue, 14 Dec 1999 13:52:57 GMT"
},
{
"version": "v3",
"created": "Wed, 30 Aug 2000 15:57:54 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Horodecki",
"Michal",
""
]
] |
quant-ph/9905059 | Helmut Kroger | H. Jirari, H. Kr\"oger, X.Q. Luo, and K.J.M. Moriarty | Monte Carlo Hamiltonian | LaTeX file (text) + 9 PS files (figures + tables) | Phys.Lett. A258 (1999) 6-14 | 10.1016/S0375-9601(99)00304-7 | null | quant-ph hep-lat | null | We construct an effective Hamiltonian via Monte Carlo from a given action.
This Hamiltonian describes physics in the low energy regime. We test it by
computing spectrum, wave functions and thermodynamical observables (average
energy and specific heat) for the free system and the harmonic oscillator. The
method is shown to work also for other local potentials.
| [
{
"version": "v1",
"created": "Wed, 19 May 1999 19:58:58 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Jirari",
"H.",
""
],
[
"Kröger",
"H.",
""
],
[
"Luo",
"X. Q.",
""
],
[
"Moriarty",
"K. J. M.",
""
]
] |
quant-ph/9905060 | Adan Cabello | Adan Cabello | Quantum correlations are not contained in the initial state | REVTeX, 4 pages, 1 figure | Phys.Rev.A60:877,1999 | 10.1103/PhysRevA.60.877 | null | quant-ph | null | Two proofs are presented which show that quantum mechanics is incompatible
with the following assumption: all possible correlations between subsystems of
an individual isolated composite quantum system are contained in the initial
quantum state of the whole system, although just a subset of them is revealed
by the actual experiment.
| [
{
"version": "v1",
"created": "Wed, 19 May 1999 20:40:06 GMT"
}
] | 2009-09-25T00:00:00 | [
[
"Cabello",
"Adan",
""
]
] |
quant-ph/9905061 | Marco Pravia | M. A. Pravia, E. Fortunato, Y. Weinstein, M. D. Price, G. Teklemariam,
R. J. Nelson, Y. Sharf, S. Somaroo, C. H. Tseng, T. F. Havel, D. G. Cory | Observations of Quantum Dynamics by Solution-State NMR Spectroscopy | 17 pages, 9 figures | Concepts Magn.Res. 11 (1999) 225-238 | null | null | quant-ph | null | NMR is emerging as a valuable testbed for the investigation of foundational
questions in quantum mechanics. The present paper outlines the preparation of a
class of mixed states, called pseudo-pure states, that emulate pure quantum
states in the highly mixed environment typically used to describe
solution-state NMR samples. It also describes the NMR observation of spinor
behavior in spin 1/2 nuclei, the simulation of wave function collapse using a
magnetic field gradient, the creation of entangled (or Bell) pseudo-pure
states, and a brief discussion of quantum computing logic gates, including the
Quantum Fourier Transform. These experiments show that liquid-state NMR can be
used to demonstrate quantum dynamics at a level suitable for laboratory
exercises.
| [
{
"version": "v1",
"created": "Thu, 20 May 1999 01:01:26 GMT"
},
{
"version": "v2",
"created": "Fri, 18 Jun 1999 22:53:16 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Pravia",
"M. A.",
""
],
[
"Fortunato",
"E.",
""
],
[
"Weinstein",
"Y.",
""
],
[
"Price",
"M. D.",
""
],
[
"Teklemariam",
"G.",
""
],
[
"Nelson",
"R. J.",
""
],
[
"Sharf",
"Y.",
""
],
[
"Somaroo",
"S.",
""
],
[
"Tseng",
"C. H.",
""
],
[
"Havel",
"T. F.",
""
],
[
"Cory",
"D. G.",
""
]
] |
quant-ph/9905062 | Nicolas Gisin | N. Gisin | Bell inequality for arbitrary many settings of the analyzers | 3 pages, 1 figure | Phys.Lett. A260 (1999) 1-3 | 10.1016/S0375-9601(99)00428-4 | null | quant-ph | null | A generalization of the CHSH-Bell inequality to arbitrary many settings is
presented. The singlet state of two spin $\half$ violates this inequality for
all numbers of setting. In the limit of arbitrarily large number of settings,
the violation tends to the finite ratio $4/\pi \approx 1.27$.
| [
{
"version": "v1",
"created": "Thu, 20 May 1999 07:59:23 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Gisin",
"N.",
""
]
] |
quant-ph/9905063 | Stanley A. Bruce | S. Bruce and J. Diaz-Valdes | An approximation to the Lamb shift and hyperfine splitting as nonlinear
effective Coulomb-like interactions in the Dirac equation | null | null | null | null | quant-ph | null | The Dirac equation for the Coulomb problem is restated by incorporating a
nonlinear effective interaction into the Dirac Hamiltonian: one keeps the $1/r$
dependence for the Coulomb field, but the coupling constant is modified by a
factor depending on the n (principal quantum number) power of the mean value of
the Hamiltonian. In this simple context we study the Lamb shift and the
hyperfine splitting of the s-levels of hydrogenic atoms. We discuss to what
extent the corresponding calculations fit the energy splittings to the
appropriate order in the fine structure constant.
| [
{
"version": "v1",
"created": "Thu, 20 May 1999 15:41:14 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bruce",
"S.",
""
],
[
"Diaz-Valdes",
"J.",
""
]
] |
quant-ph/9905064 | Seth Lloyd | Seth Lloyd, Jean-Jacques E. Slotine | Quantum feedback with weak measurements | 11 pages, TeX, replaced to incorporate suggestions of Asher Peres | null | 10.1103/PhysRevA.62.012307 | null | quant-ph | null | The problem of feedback control of quantum systems by means of weak
measurements is investigated in detail. When weak measurements are made on a
set of identical quantum systems, the single-system density matrix can be
determined to a high degree of accuracy while affecting each system only
slightly. If this information is fed back into the systems by coherent
operations, the single-system density matrix can be made to undergo an
arbitrary nonlinear dynamics, including for example a dynamics governed by a
nonlinear Schr\"odinger equation. We investigate the implications of such
nonlinear quantum dynamics for various problems in quantum control and quantum
information theory, including quantum computation. The nonlinear dynamics
induced by weak quantum feedback could be used to create a novel form of
quantum chaos in which the time evolution of the single-system wave function
depends sensitively on initial conditions.
| [
{
"version": "v1",
"created": "Thu, 20 May 1999 15:55:21 GMT"
},
{
"version": "v2",
"created": "Sun, 5 Dec 1999 21:52:56 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Lloyd",
"Seth",
""
],
[
"Slotine",
"Jean-Jacques E.",
""
]
] |
quant-ph/9905065 | Robert Clifton | Rob Clifton (Depts. of Philosophy and History and Philosophy of
Science, University of Pittsburgh), Bradley Monton (Dept. of Philosophy
Princeton University) | Losing Your Marbles in Wavefunction Collapse Theories | 30 pages, LaTeX, To be published in the December 1999 issue of The
British Journal for Philosophy of Science | null | null | null | quant-ph | null | Peter Lewis ([1997]) has recently argued that the wavefunction collapse
theory of GRW (Ghirardi, Rimini, and Weber [1986]) can only solve the problem
of wavefunction tails at the expense of predicting that arithmetic does not
apply to ordinary macroscopic objects. More specifically, Lewis argues that the
GRW theory must violate the enumeration principle: that `if marble 1 is in the
box and marble 2 is in the box and so on through marble $n$, then all $n$
marbles are in the box' ([1997], p. 321). Ghirardi and Bassi ([1999]) have
replied that it is meaningless to say that the enumeration principle is
violated because the wavefunction Lewis uses to exhibit the violation cannot
persist, according to the GRW theory, for more than a split second ([1999], p.
709). On the contrary, we argue that Lewis's argument survives Ghirardi and
Bassi's criticism unscathed. We then go on to show that, while the enumeration
principle can fail in the GRW theory, the theory itself guarantees that the
principle can never be empirically falsified, leaving the applicability of
arithmetical reasoning to both micro- and macroscopic objects intact.
| [
{
"version": "v1",
"created": "Thu, 20 May 1999 19:23:26 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Clifton",
"Rob",
"",
"Depts. of Philosophy and History and Philosophy of\n Science, University of Pittsburgh"
],
[
"Monton",
"Bradley",
"",
"Dept. of Philosophy\n Princeton University"
]
] |
quant-ph/9905066 | Hayashi Masahito | Fuminori Sakaguchi (Fukui University), Masahito Hayashi (Kyoto
University) | su(1,1) coherent states and a normal extension of su(1,1) annihilation
operator: squeezed states and the simultaneous measurement of Q^{-1}P+PQ^{-1}
and Q^{-2} | LaTeX2e. 13 pages | null | null | null | quant-ph | null | The the over-complete eigenvector system of the operator Q^{-1}P (Q:position,
P:momentum) which consists of the squeezed states |0; s, t > with various s and
t are investigated from the viewpoint of the annihilation and creation
relations related to the algebra su(1,1). We derive a positive operator-valued
measure(POVM) for the simultaneous measurement between the self-adjoint and
anti-self-adjoint parts of PQ^{-1}.
| [
{
"version": "v1",
"created": "Fri, 21 May 1999 07:43:02 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Sakaguchi",
"Fuminori",
"",
"Fukui University"
],
[
"Hayashi",
"Masahito",
"",
"Kyoto\n University"
]
] |
quant-ph/9905067 | Ozgur E. Mustecaplioglu | \"Ozg\"ur E. M\"ustecapl{\i}o\u{g}lu and Alexander S. Shumovsky | Statistics of Raman-Active Excitations via Masurement of
Stokes-Anti-Stokes Correlations | 12 pages, 1 figure, accepted for publication in Phys.Rev.B | null | 10.1103/PhysRevB.60.3970 | null | quant-ph | null | A general fundamental relation connecting the correlation of Stokes and
anti-Stokes modes to the quantum statistical behavior of vibration and pump
modes in Raman-active materials is derived. We show that under certain
conditions this relation can be used to determine the equilibrium number
variance of phonons.Time and temperature ranges for which such conditions can
be satisfied are studied and found to be available in todays' experimental
standards. Furthermore, we examine the results in the presence of multi-mode
pump as well as for the coupling of pump to the many vibration modes and
discuss their validity in these cases.
| [
{
"version": "v1",
"created": "Fri, 21 May 1999 10:21:34 GMT"
}
] | 2016-08-15T00:00:00 | [
[
"Müstecaplıoğlu",
"Özgür E.",
""
],
[
"Shumovsky",
"Alexander S.",
""
]
] |
quant-ph/9905068 | Christian Helm | H. Geiger, G. Obermair, Ch. Helm | Quantum mechanics without statistical postulates | Latex,elsart preprint style, 14 pages, 4 figures | null | null | null | quant-ph chao-dyn nlin.CD | null | The Bohmian formulation of quantum mechanics is used in order to describe the
measurement process in an intuitive way without a reduction postulate in the
framework of a deterministic single system theory. Thereby the motion of the
hidden classical particle is chaotic during almost all nontrivial measurement
processes. For the correct reproduction of experimental results, it is further
essential that the distribution function $P(x)$ of the results of a position
measurement is identical with $|\Psi|^2$ of the wavefunction $\Psi$ of the
single system under consideration. It is shown that this feature is not an
additional assumption, but can be derived strictly from the chaotic motion of a
single system during a sequence of measurements, providing a completely
deterministic picture of the statistical features of quantum mechanics.
| [
{
"version": "v1",
"created": "Fri, 21 May 1999 13:49:17 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Geiger",
"H.",
""
],
[
"Obermair",
"G.",
""
],
[
"Helm",
"Ch.",
""
]
] |
quant-ph/9905069 | Alexandre Tort | D. T. Alves, C. Farina and A. C. Tort | Spontaneous emission between an unusual pair of plates | latex file 4 pages, 4 figures | Phys.Rev. A61 (2000) 034102 | 10.1103/PhysRevA.61.034102 | fit/if/ufrj 002-99 | quant-ph | null | We compute the modification in the spontaneous emission rate for a two-level
atom when it is located between two parallel plates of different nature: a
perfectly conducting plate $(\epsilon\to \infty)$ and an infinitely permeable
one $(\mu\to \infty)$. We also discuss the case of two infinitely permeable
plates. We compare our results with those found in the literature for the case
of two perfectly conducting plates.
| [
{
"version": "v1",
"created": "Fri, 21 May 1999 20:22:24 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Alves",
"D. T.",
""
],
[
"Farina",
"C.",
""
],
[
"Tort",
"A. C.",
""
]
] |
quant-ph/9905070 | Marco Frasca | Marco Frasca | Perturbative study of multiphoton processes in the tunneling regime | Latex, 11 pages. To appear on Phys. Lett. A | Phys.Lett. A260 (1999) 149-155 | 10.1016/S0375-9601(99)00487-9 | null | quant-ph hep-ph hep-th physics.atom-ph | null | A perturbative study of the Schr\"{o}dinger equation in a strong
electromagnetic field with dipole approximation is accomplished in the
Kramers-Henneberger frame. A prove that just odd harmonics appear in the
spectrum for a linear polarized laser field is given, assuming that the atomic
radius is much lesser than the free-electron quiver motion amplitude. Within
this approximation a perturbation series is obtained in the Keldysh parameter
giving a description of multiphoton processes in the tunneling regime. The
theory is applied to the case of hydrogen-like atoms: The spectrum of higher
order harmonics and the above-threshold ionization rate are derived. The
ionization rate computed in this way determines the amplitudes of the
harmonics. The wave function of the atom proves to be rigid with respect to the
perturbation so that the effect of the laser field on the Coulomb potential in
the computation of the probability amplitudes can be neglected as a first
approximation: This approximation improves as the ratio between the amplitude
of the quiver motion of the electron and the atom radius becomes larger. The
semiclassical description currently adopted for harmonic generation is so
rederived by solving perturbatively the Schr\"{o}dinger equation.
| [
{
"version": "v1",
"created": "Sat, 22 May 1999 18:07:43 GMT"
},
{
"version": "v2",
"created": "Thu, 29 Jul 1999 19:51:52 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Frasca",
"Marco",
""
]
] |
quant-ph/9905071 | Daniel Jonathan | Daniel Jonathan and Martin B. Plenio | Entanglement-assisted local manipulation of pure quantum states | Published version, including important changes | Phys.Rev.Lett.83:3566-3569,1999 | 10.1103/PhysRevLett.83.3566 | null | quant-ph | null | We demonstrate that local transformations on a composite quantum system can
be enhanced in the presence of certain entangled states. These extra states act
much like catalysts in a chemical reaction: they allow otherwise impossible
local transformations to be realised, without being consumed in any way. In
particular, we show that this effect can considerably improve the efficiency of
entanglement concentration procedures for finite states.
| [
{
"version": "v1",
"created": "Sat, 22 May 1999 18:59:06 GMT"
},
{
"version": "v2",
"created": "Mon, 6 Dec 1999 17:50:40 GMT"
}
] | 2009-01-23T00:00:00 | [
[
"Jonathan",
"Daniel",
""
],
[
"Plenio",
"Martin B.",
""
]
] |
quant-ph/9905072 | Dr. Y. C. Huang | Y. C. Huang | Unified Expressions of Physical Fundamental Interactions and Variational
Principles Based On The Quantitative Causal Principle | This paper has been withdrawn | null | null | Beijing Polytechnic University BJPU99-4 | quant-ph | null | This paper has been withdrawn by the authors because the paper is largely
revised and improved.
| [
{
"version": "v1",
"created": "Sun, 23 May 1999 20:41:44 GMT"
},
{
"version": "v2",
"created": "Thu, 8 May 2003 04:20:09 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Huang",
"Y. C.",
""
]
] |
quant-ph/9905073 | Wen-Fa Lu | Wen-Fa Lu, (Shanghai Jiao Tong University) | Thermalized Displaced Squeezed Thermal States | 7 pages, no figures, Revtex file | J.Phys.A33:479-486,2000 | 10.1088/0305-4470/33/3/304 | null | quant-ph | null | In the coordinate representation of thermofield dynamics, we investigate the
thermalized displaced squeezed thermal state which involves two temperatures
successively. We give the wavefunction and the matrix element of the density
operator at any time, and accordingly calculate some quantities related to the
position, momentum and particle number operator, special cases of which are
consistent with the results in the literature. The two temperatures have
diffenent correlations with the squeeze and coherence components. Moreover,
different from the properties of the position and momentum, the average value
and variance of the particle number operator as well as the second-order
correlation function are time-independent.
| [
{
"version": "v1",
"created": "Mon, 24 May 1999 02:45:07 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Lu",
"Wen-Fa",
""
]
] |
quant-ph/9905074 | Stanley A. Bruce | S. Bruce et. al | Unbroken supersymmetry in the Aharonov-Casher effect | null | null | 10.1103/PhysRevA.60.R1 | null | quant-ph | null | We consider the problem of the bound states of a spin 1/2 chargless particle
in a given Aharonov-Casher configuration. To this end we recast the description
of the system in a supersymmetric form. Then the basic physical requirements
for unbroken supersymmetry are established. We comment on the possibility of
neutron confinement in this system.
| [
{
"version": "v1",
"created": "Mon, 24 May 1999 13:33:46 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"al",
"S. Bruce et.",
""
]
] |
quant-ph/9905075 | Stanley A. Bruce | S. Bruce and L. Roa | The ground state of a spin-1/2 neutral particle with anomalous magnetic
moment in a Aharonov-Casher configuration | null | Europhys.Lett. 46 (1999) 703-709 | 10.1209/epl/i1999-00322-3 | null | quant-ph | null | We determine the (bound) ground state of a spin 1/2 chargless particle with
anomalous magnetic moment in certain Aharonov-Casher configurations. We recast
the description of the system in a supersymmetric form. Then the basic physical
requirements for unbroken supersymmetry are established. We comment on the
possibility of neutron trapping in these systems.
| [
{
"version": "v1",
"created": "Mon, 24 May 1999 13:52:17 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Bruce",
"S.",
""
],
[
"Roa",
"L.",
""
]
] |
quant-ph/9905076 | Norman Dombey | A Calogeracos and N Dombey | History and Physics of the Klein Paradox | To be Published in Contemporary Physics | Contemp.Phys. 40 (1999) 313-321 | 10.1080/001075199181387 | SUSX-TH-99-032 | quant-ph | null | The early papers by Klein, Sauter and Hund which investigate scattering off a
high step potential in the context of the Dirac equation are discussed to
derive the 'paradox' first obtained by Klein. The explanation of this effect in
terms of electron-positron production is reassessed. It is shown that a
potential well or barrier in the Dirac equation can become supercritical and
emit positrons or electrons spontaneously if the potential is strong enough. If
the well or barrier is wide enough, a seemingly constant current is emitted.
This phenomenon is transient whereas the tunnelling first calculated by Klein
is time-independent. It is shown that tunnelling without exponential
suppression occurs when an electron is incident on a high barrier, even when
the barrier is not high enough to radiate. Klein tunnelling is therefore a
property of relativistic wave equations and is not necessarily connected to
particle emission. The Coulomb potential is investigated and it is shown that a
heavy nucleus of sufficiently large $Z$ will bind positrons. Correspondingly,
as $Z$ increases the Coulomb barrier should become increasingly transparent to
positrons. This is an example of Klein tunnelling. Phenomena akin to
supercritical positron emission may be studied experimentally in superfluid
$^3$He
| [
{
"version": "v1",
"created": "Mon, 24 May 1999 14:04:45 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Calogeracos",
"A",
""
],
[
"Dombey",
"N",
""
]
] |
quant-ph/9905077 | James Ax | James Ax and Simon Kochen | Extension of Quantum Mechanics to Individual Systems | Latex+pb-diagram, 77 pages + 10 figures. Many minor corrections, more
and better figures. IQM.ps may be more inter-system reliable than IQM.pdf.
Additional and animated graphics are available at:
http://www.princeton.edu/~jimax/iqm.html This site also contains and invites
informal discussion of related ideas to be sent to the CORRECTED email
address: [email protected] or [email protected] | null | null | null | quant-ph math-ph math.MP | null | The Copenhagen Interpretation describes individual systems, using the same
Hilbert space formalism as does the statistical ensemble interpretation (SQM).
This leads to the well-known paradoxes surrounding the Measurement Problem. We
extend this common mathematical structure to encompass certain natural bundles
with connections over the Hilbert sphere S. This permits a consistent extension
of the statistical interpretation to interacting individual systems, thereby
resolving these paradoxes.
Suppose V is a physical system in interaction with another system W. The
state vector of V+W has a set of polar decompositions with a vector q of
complex coefficients. These are parameterized by the right toroid T of
amplitudes q, and comprise a singular toroidal bundle over S, which comprises
the enlarged state space of V+W. We prove that each T has a unique natural
convex partition yielding the correct SQM probabilities. In the extended theory
V and W synchronously assume pure spectral states according to which member of
the partition contains q. The apparent indeterminism of SQM is thus
attributable to the effectively random distribution of initial phases.
| [
{
"version": "v1",
"created": "Mon, 24 May 1999 22:50:26 GMT"
},
{
"version": "v2",
"created": "Mon, 14 Jun 1999 20:46:44 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Ax",
"James",
""
],
[
"Kochen",
"Simon",
""
]
] |
quant-ph/9905078 | Stanley A. Bruce | S. Bruce | How to build a non-spreading wave packet in quantum mechanics | null | null | null | null | quant-ph | null | Quantum mechanics asserts that a wave packet must inevitably spread as time
progresses since the dispersion relation for the quantum waves is assumed to be
quadratic in the momentum k. However, this assumption does not consider the
standard frequency Doppler shift formula of Galilean relativity. In this
article a non-dispersive wave packet is constructed by appropriately
considering the transformation rules between the laboratory and the
(particle's) rest inertial reference frames.
| [
{
"version": "v1",
"created": "Mon, 24 May 1999 20:34:19 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bruce",
"S.",
""
]
] |
quant-ph/9905079 | Todd A. Brun | Todd A. Brun (ITP, UCSB; CMU), James B. Hartle (Physics and ITP, UCSB) | Classical Dynamics of the Quantum Harmonic Chain | 38 pages RevTeX 3.0 + 4 figures (postscript). Numerous minor
corrections. Submitted to Physical Review D | Phys.Rev. D60 (1999) 123503 | 10.1103/PhysRevD.60.123503 | NSF-ITP-99-34 | quant-ph gr-qc | null | The origin of classical predictability is investigated for the one
dimensional harmonic chain considered as a closed quantum mechanical system. By
comparing the properties of a family of coarse-grained descriptions of the
chain, we conclude that local coarse-grainings in this family are more useful
for prediction than nonlocal ones. A quantum mechanical system exhibits
classical behavior when the probability is high for histories having the
correlations in time implied by classical deterministic laws. But approximate
classical determinism holds only for certain coarse-grainings and then only if
the initial state of the system is suitably restricted. Coarse-grainings by the
values of the hydrodynamic variables (integrals over suitable volumes of
densities of approximately conserved quantities) define the histories usually
used in classical physics. But what distinguishes this coarse-graining from
others? This paper approaches this question by analyzing a family of
coarse-grainings for the linear harmonic chain. At one extreme in the family
the chain is divided into local groups of $N$ atoms. At the other extreme the
$N$ atoms are distributed nonlocally over the whole chain. Each coarse-graining
follows the average (center of mass) positions of the groups and ignores the
``internal'' coordinates within each group, these constituting a different
environment for each coarse-graining. We conclude that noise, decoherence, and
computational complexity favor locality over nonlocality for deterministic
predictability.
| [
{
"version": "v1",
"created": "Mon, 24 May 1999 21:12:58 GMT"
},
{
"version": "v2",
"created": "Tue, 25 May 1999 18:06:18 GMT"
},
{
"version": "v3",
"created": "Thu, 5 Aug 1999 22:45:12 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Brun",
"Todd A.",
"",
"ITP, UCSB; CMU"
],
[
"Hartle",
"James B.",
"",
"Physics and ITP, UCSB"
]
] |
quant-ph/9905080 | David Meyer | David A. Meyer (University of California/San Diego) | Finite precision measurement nullifies the Kochen-Specker theorem | 7 pages, plain TeX; minor corrections, interpretation clarified,
references updated | Phys.Rev.Lett.83:3751-3754,1999 | 10.1103/PhysRevLett.83.3751 | null | quant-ph math-ph math.MP | null | Only finite precision measurements are experimentally reasonable, and they
cannot distinguish a dense subset from its closure. We show that the rational
vectors, which are dense in S^2, can be colored so that the contradiction with
hidden variable theories provided by Kochen-Specker constructions does not
obtain. Thus, in contrast to violation of the Bell inequalities, no
quantum-over-classical advantage for information processing can be derived from
the Kochen-Specker theorem alone.
| [
{
"version": "v1",
"created": "Mon, 24 May 1999 21:57:07 GMT"
},
{
"version": "v2",
"created": "Mon, 20 Sep 1999 19:05:02 GMT"
}
] | 2009-01-23T00:00:00 | [
[
"Meyer",
"David A.",
"",
"University of California/San Diego"
]
] |
quant-ph/9905081 | Steven J. van Enk | S.J. van Enk | Discrete formulation of teleportation of continuous variables | Important reference included: L. Vaidman, Phys Rev A 49, 1473 (1994) | Phys Rev A 60, 5095 (1999) | 10.1103/PhysRevA.60.5095 | null | quant-ph | null | Teleportation of continuous variables can be described in two different ways,
one in terms of Wigner functions, the other in terms of discrete basis states.
The latter formulation provides the connection between the theory of
teleportation of continuous degrees of freedom of a light field and the
standard description of teleportation of discrete variables.
| [
{
"version": "v1",
"created": "Mon, 24 May 1999 23:25:01 GMT"
},
{
"version": "v2",
"created": "Fri, 4 Feb 2000 18:21:24 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"van Enk",
"S. J.",
""
]
] |
quant-ph/9905082 | Alec Maassen van den Brink | Alec Maassen van den Brink (Department of Physics, The Chinese
University of Hong Kong, Hong Kong, China) | Exactly solvable path integral for open cavities in terms of quasinormal
modes | REVTeX, 26 pages, submitted to Phys. Rev. E | Phys.Rev.E61:2367-2375,2000 | 10.1103/PhysRevE.61.2367 | null | quant-ph | null | We evaluate the finite-temperature Euclidean phase-space path integral for
the generating functional of a scalar field inside a leaky cavity. Provided the
source is confined to the cavity, one can first of all integrate out the fields
on the outside to obtain an effective action for the cavity alone.
Subsequently, one uses an expansion of the cavity field in terms of its
quasinormal modes (QNMs)-the exact, exponentially damped eigenstates of the
classical evolution operator, which previously have been shown to be complete
for a large class of models. Dissipation causes the effective cavity action to
be nondiagonal in the QNM basis. The inversion of this action matrix inherent
in the Gaussian path integral to obtain the generating functional is therefore
nontrivial, but can be accomplished by invoking a novel QNM sum rule. The
results are consistent with those obtained previously using canonical
quantization.
| [
{
"version": "v1",
"created": "Tue, 25 May 1999 03:09:09 GMT"
}
] | 2008-12-18T00:00:00 | [
[
"Brink",
"Alec Maassen van den",
"",
"Department of Physics, The Chinese\n University of Hong Kong, Hong Kong, China"
]
] |
quant-ph/9905083 | Fu Li Ping | Liping Fu, Jun Luo, Li Xiao and Xizhi Zeng (Laboratory of Magnetic
Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and
Mathematics, The Chinese Academy of Sciences, Wuhan, People's Republic of
China) | Experimental Realization of Discrete Fourier Transformation on NMR
Quantum Computer | Latex, 6 pages, 3 figures on two seperate papers | null | null | null | quant-ph | null | We report experimental implementation of discrete Fourier transformation(DFT)
on a nuclear magnetic resonance(NMR) quantum computer. Experimental results
agree with theoretical results. Using the pulse sequences we introduced, DFT
can be realized on any L-bit quantum number in principle.
| [
{
"version": "v1",
"created": "Tue, 25 May 1999 09:47:56 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Fu",
"Liping",
"",
"Laboratory of Magnetic\n Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and\n Mathematics, The Chinese Academy of Sciences, Wuhan, People's Republic of\n China"
],
[
"Luo",
"Jun",
"",
"Laboratory of Magnetic\n Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and\n Mathematics, The Chinese Academy of Sciences, Wuhan, People's Republic of\n China"
],
[
"Xiao",
"Li",
"",
"Laboratory of Magnetic\n Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and\n Mathematics, The Chinese Academy of Sciences, Wuhan, People's Republic of\n China"
],
[
"Zeng",
"Xizhi",
"",
"Laboratory of Magnetic\n Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and\n Mathematics, The Chinese Academy of Sciences, Wuhan, People's Republic of\n China"
]
] |
quant-ph/9905084 | Asher Peres | Asher Peres | Bayesian analysis of Bell inequalities | 8 pages, LaTeX, PostScript figue on separate page | Fortsch.Phys. 48 (2000) 531-535 | 10.1002/(SICI)1521-3978(200005)48:5/7<531::AID-PROP531>3.0.CO;2-# | null | quant-ph | null | Statistical tests are needed to determine experimentally whether a
hypothetical theory based on local realism can be an acceptable alternative to
quantum mechanics. It is impossible to rule out local realism by a single test,
as often claimed erroneously. The ``strength'' of a particular Bell inequality
is measured by the number of trials that are needed to invalidate local realism
at a given confidence level. Various versions of Bell's inequality are compared
from this point of view. It is shown that Mermin's inequality for
Greenberger-Horne-Zeilinger states requires fewer tests than the
Clauser-Horne-Shimony-Holt inequality or than its chained variants applied to a
singlet state, and also than Hardy's proof of nonlocality.
| [
{
"version": "v1",
"created": "Tue, 25 May 1999 12:00:37 GMT"
}
] | 2017-04-26T00:00:00 | [
[
"Peres",
"Asher",
""
]
] |
quant-ph/9905085 | Jens Clausen | J. Clausen, M. Dakna, L. Knoell, D.-G. Welsch | Conditional quantum state engineering at beam splitter arrays | 6 pages, 3 figures, contribution to proceedings of the 6th
central-european workshop on quantum optics | Acta Phys. Slov. 49, 653 (1999) | null | null | quant-ph | null | The generation of arbitrary single-mode quantum states from the vacuum by
alternate coherent displacement and photon adding as well as the measurement of
the overlap of a signal with an arbitrarily chosen quantum state are studied.
With regard to implementations, the transformation of the quantum state of a
traveling optical field at an array of beam splitters is considered, using
conditional measurement. Allowing for arbitrary quantum states of both the
input reference modes and the output reference modes on which the measurements
are performed, the setup is described within the concept of two-port
non-unitary transformation, and the overall non-unitary transformation operator
is derived. It is shown to be a product of operators, where each operator is
assigned to one of the beam splitters and can be expressed in terms of an
s-ordered operator product, with s being determined by the beam splitter
transmittance or reflectance. As an example we discuss the generation of and
overlap measurement with Schroedinger-cat-like states.
| [
{
"version": "v1",
"created": "Tue, 25 May 1999 14:39:28 GMT"
}
] | 2016-05-17T00:00:00 | [
[
"Clausen",
"J.",
""
],
[
"Dakna",
"M.",
""
],
[
"Knoell",
"L.",
""
],
[
"Welsch",
"D. -G.",
""
]
] |
quant-ph/9905086 | Andrew G. White | P. G. Kwiat, J. R. Mitchell, P. D. D. Schwindt, and A. G. White (Los
Alamos National Laboratory, USA) | Grover's search algorithm: An optical approach | 6 pages, 5 figures. To appear in a special issue of the Journal of
Modern Optics -- "The Physics of Quantum Information" | Journal of Modern Optics 47, 257-266 (2000) | 10.1080/09500340008244040 | null | quant-ph | null | The essential operations of a quantum computer can be accomplished using
solely optical elements, with different polarization or spatial modes
representing the individual qubits. We present a simple all-optical
implementation of Grover's algorithm for efficient searching, in which a
database of four elements is searched with a single query. By `compiling' the
actual setup, we have reduced the required number of optical elements from 24
to only 12. We discuss the extension to larger databases, and the limitations
of these techniques.
| [
{
"version": "v1",
"created": "Tue, 25 May 1999 17:50:25 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Kwiat",
"P. G.",
"",
"Los\n Alamos National Laboratory, USA"
],
[
"Mitchell",
"J. R.",
"",
"Los\n Alamos National Laboratory, USA"
],
[
"Schwindt",
"P. D. D.",
"",
"Los\n Alamos National Laboratory, USA"
],
[
"White",
"A. G.",
"",
"Los\n Alamos National Laboratory, USA"
]
] |
quant-ph/9905087 | John M. Myers | R. Marx, A. F. Fahmy, J. M. Myers, W. Bermel, S. J. Glaser | Realization of a 5-bit NMR Quantum Computer Using a New Molecular
Architecture | 7 pages, 4 figures, 1 table | null | null | null | quant-ph | null | We demonstrate a five-bit nuclear-magnetic-resonance quantum computer that
distinguishes among various functions on four bits, making use of quantum
parallelism. Its construction draws on the recognition of the sufficiency of
linear coupling along a chain of nuclear spins, the synthesis of a suitably
coupled molecule, and the use of a multi-channel spectrometer.
| [
{
"version": "v1",
"created": "Tue, 25 May 1999 19:58:24 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Marx",
"R.",
""
],
[
"Fahmy",
"A. F.",
""
],
[
"Myers",
"J. M.",
""
],
[
"Bermel",
"W.",
""
],
[
"Glaser",
"S. J.",
""
]
] |
quant-ph/9905088 | Emil Vasile Prodan | E. Prodan | Gaussian, Mean Field and Variational Approximation: the Equivalence | 18 pages, no figure | null | null | null | quant-ph | null | We show the equivalence between the three approximation schemes for
self-interacting (1+1)-D scalar field theories. Based on rigorous results of
[1, 2], we are able to prove that the Gaussian approximation is very precise
for certain limits of coupling constants. The $\lambda \phi ^{4}+\sigma \phi
^{2}$ model will be used as a concrete application.
| [
{
"version": "v1",
"created": "Wed, 26 May 1999 01:53:52 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Prodan",
"E.",
""
]
] |
quant-ph/9905089 | John Samson | J H Samson | Exact Classical Effective Potential | 4 pages | Proceedings of Sixth International Conference on Path Integrals
from peV to TeV, Firenze, eds R Casalbuoni et al (World Scientific 1999),
550-553 | null | null | quant-ph cond-mat.stat-mech | null | A quantum spin system can be modelled by an equivalent classical system, with
an effective Hamiltonian obtained by integrating all non-zero frequency modes
out of the path integral. The effective Hamiltonian H_eff(S_i) derived from the
coherent-state integral is highly singular: the quasiprobability density
exp(-beta H_eff), a Wigner function, imposes quantisation through derivatives
of delta functions. This quasiprobability is the distribution of the
time-averaged lower symbol of the spin in the coherent-state integral. We
relate the quantum Monte Carlo minus-sign problem to the non-positivity of this
quasiprobability, both analytically and by Monte Carlo integration.
| [
{
"version": "v1",
"created": "Wed, 26 May 1999 15:54:36 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Samson",
"J H",
""
]
] |
quant-ph/9905090 | Thorsten Koehler | Gerhard C. Hegerfeldt and Thorsten Koehler | Theoretical challenges in atom optics: Atomic and molecular diffraction
by transmission gratings | 10 pages LaTeX + 4 figures | null | null | null | quant-ph | null | A few years ago, diffraction of atoms by double slits and gratings was
achieved for the first time, and standard optical wave-theory provided an
excellent description of the experiments. More recently, diffraction of weakly
bound molecules and even clusters has been observed. Due to their size and to
possible breakup processes optical wave-theory is no longer adequate and a more
sophisticated approach is needed. Moreover, surface effects, which can modify
the diffraction pattern of atoms and molecules, give rise to further
complications. In this article a fully quantum mechanical approach to these
questions is discussed.
| [
{
"version": "v1",
"created": "Wed, 26 May 1999 16:20:18 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Hegerfeldt",
"Gerhard C.",
""
],
[
"Koehler",
"Thorsten",
""
]
] |
quant-ph/9905091 | Konstantin B. Korotchenko | K.B. Korotchenko | Quantum mechanics in the K-Field formalism: the basic principles of
geometrization | 6 pages, LaTeX2e | null | null | null | quant-ph hep-th | null | The basic principles of the quantum mechanics in the K-field formalism are
stated in the paper. The basic distinction of this theory arises from that the
quantum theory equations (including well-known Schrodinger, Klein-Gordon and
quadratic Dirac equations) are obtained from de Broglie postulate geometric
generalization. Rather, they are obtained as the free wave equations on a
manifold metrizing force interactions of particles. Such view on the quantum
theory basic equations allows one to use semiclassical models for the quantum
system simulation. The quantization principle modifies as well. Namely, quantum
system stationary conditions are such conditions, at which test particles
motion is Lyapunov stable.
| [
{
"version": "v1",
"created": "Thu, 27 May 1999 08:33:21 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Korotchenko",
"K. B.",
""
]
] |
quant-ph/9905092 | Rusins Freivalds | Maksim Kravtsev (University of Latvia) | Quantum Finite One-Counter Automata | 11 pages, Postscript | null | null | null | quant-ph | null | In this paper the notion of quantum finite one-counter automata (QF1CA) is
introduced. Introduction of the notion is similar to that of the 2-way quantum
finite state automata by A.Kondacs and J.Watrous. The well-formedness
conditions for the automata are specified ensuring unitarity of evolution. A
special kind of QF1CA, called simple, that satisfies the well-formedness
conditions is introduced. That allows to specify rules for constructing such
automata more naturally and simpler than in general case. Possible models of
language recognition by QF1CA are considered. The recognition of some languages
by QF1CA is shown and compared with recognition by probabilistic counterparts.
| [
{
"version": "v1",
"created": "Thu, 27 May 1999 13:03:29 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Kravtsev",
"Maksim",
"",
"University of Latvia"
]
] |
quant-ph/9905093 | Marc-Thierry Jaekel | Marc-Thierry Jaekel (Laboratoire de Physique The'orique de l'Ecole
Normale Supe'rieure) and Serge Reynaud (Laboratoire Kastler Brossel) | Quantum Hexaspherical Observables for Electrons | 9 pages | Annalen Phys. 9 (2000) 589-604 | 10.1002/1521-3889(200009)9:8<589::AID-ANDP589>3.0.CO;2-# | LPTENS 99/18 | quant-ph gr-qc | null | A new quantum algebraic description of relativistic electrons, built on a
conformal dynamical symmetry (SO(4,2)), has recently been proposed to treat
localization in space-time. It is shown here that localization of an electron
may be represented by components of a SO(4,2) vector which are quantum
generalizations of the hexaspherical coordinates of classical projective
geometry. The shift of this vector under transformations to uniformly
accelerated frames is described by SO(4,2) rotations. Hexaspherical observables
also allow one to represent the quantum law of free fall under a form
explicitly compatible with the same dynamical symmetry.
| [
{
"version": "v1",
"created": "Thu, 27 May 1999 13:21:15 GMT"
}
] | 2017-09-27T00:00:00 | [
[
"Jaekel",
"Marc-Thierry",
"",
"Laboratoire de Physique The'orique de l'Ecole\n Normale Supe'rieure"
],
[
"Reynaud",
"Serge",
"",
"Laboratoire Kastler Brossel"
]
] |
quant-ph/9905094 | Jonathan Halliwell | J. J. Halliwell | Decoherent Histories and the Emergent Classicality of Local Densities | 12 pages, plain Tex, third revision with new, PRL-friendly Title
(previously released as ``Histories of Local Densities Don't Interefere'') | Phys.Rev.Lett. 83 (1999) 2481 | 10.1103/PhysRevLett.83.2481 | null | quant-ph | null | In the context of the decoherent histories approach to quantum theory, it is
shown that a class of macroscopic configurations consisting of histories of
local densities (number, momentum, energy) exhibit negligible interference.
This follows from the close connection of the local densities with the
corresponding exactly conserved (and so exactly decoherent) quantities, and
also from the observation that the eigenstates of local densities (averaged
over a sufficiently large volume) remain approximate eigenstates under time
evolution. The result is relevant to the derivation of hydrodynamic equations
using the decoherent histories approach.
| [
{
"version": "v1",
"created": "Thu, 27 May 1999 15:38:06 GMT"
},
{
"version": "v2",
"created": "Wed, 2 Jun 1999 12:31:31 GMT"
},
{
"version": "v3",
"created": "Tue, 17 Aug 1999 16:31:50 GMT"
},
{
"version": "v4",
"created": "Tue, 7 Dec 1999 18:00:21 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Halliwell",
"J. J.",
""
]
] |
quant-ph/9905095 | Jose L. Cereceda | Jose L. Cereceda | Two-particle entanglement as a property of three-particle entangled
states | REVTeX, 7 pages, no figures | Phys.Rev.A56:1733-1738,1997 | 10.1103/PhysRevA.56.1733 | null | quant-ph | null | In a recent article [Phys. Rev. A 54, 1793 (1996)] Krenn and Zeilinger
investigated the conditional two-particle correlations for the subensemble of
data obtained by selecting the results of the spin measurements by two
observers 1 and 2 with respect to the result found in the corresponding
measurement by a third observer. In this paper we write out explicitly the
condition required in order for the selected results of observers 1 and 2 to
violate Bell's inequality for general measurement directions. It is shown that
there are infinitely many sets of directions giving the maximum level of
violation. Further, we extend the analysis by the authors to the class of
triorthogonal states |Psi> = c_1 |z_1>|z_2>|z_3> + c_2 |-z_1>|-z_2>|-z_3>. It
is found that a maximal violation of Bell's inequality occurs provided the
corresponding three-particle state yields a direct ("all or nothing")
nonlocality contradiction.
| [
{
"version": "v1",
"created": "Thu, 27 May 1999 21:47:19 GMT"
}
] | 2008-12-18T00:00:00 | [
[
"Cereceda",
"Jose L.",
""
]
] |
quant-ph/9905096 | Rutger Vrijen | Rutger Vrijen, Eli Yablonovitch, Kang Wang, Hong Wen Jiang, Alex
Balandin, Vwani Roychowdhury, Tal Mor and David DiVincenzo | Electron Spin Resonance Transistors for Quantum Computing in
Silicon-Germanium Heterostructures | 10 pages LaTex, incl. 15 Figures 6/11/99 Added: discussion of
g-factor and T1 and T2 of donor electron spin in Ge with related references,
1 figure and a discussion of ion implantation statistics in large arrays | null | 10.1103/PhysRevA.62.012306 | null | quant-ph | null | We apply the full power of modern electronic band structure engineering and
epitaxial heterostructures to design a transistor that can sense and control a
single donor electron spin. Spin resonance transistors may form the
technological basis for quantum information processing. One and two qubit
operations are performed by applying a gate bias. The bias electric field pulls
the electron wave function away from the dopant ion into layers of different
alloy composition. Owing to the variation of the g-factor (Si:g=1.995,
Ge:g=1.563), this displacement changes the spin Zeeman energy, allowing
single-qubit operations. By displacing the electron even further, the overlap
with neighboring qubits is affected, which allows two-qubit operations. Certain
Silicon-Germanium alloys allow a qubit spacing as large as 200 nm, which is
well within the capabilities of current lithographic techniques. We discuss
manufacturing limitations and issues regarding scaling up to a large size
computer.
| [
{
"version": "v1",
"created": "Fri, 28 May 1999 00:06:19 GMT"
},
{
"version": "v2",
"created": "Fri, 11 Jun 1999 23:34:02 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Vrijen",
"Rutger",
""
],
[
"Yablonovitch",
"Eli",
""
],
[
"Wang",
"Kang",
""
],
[
"Jiang",
"Hong Wen",
""
],
[
"Balandin",
"Alex",
""
],
[
"Roychowdhury",
"Vwani",
""
],
[
"Mor",
"Tal",
""
],
[
"DiVincenzo",
"David",
""
]
] |
quant-ph/9905097 | Tony Bracken | A.J. Bracken (ASI, TU-Clausthal), H.-D. Doebner (ASI, TU-Clausthal),
J.G. Wood (University of Queensland) | Bounds on Integrals of the Wigner Function | 10 pages, 1 PostScript figure, Latex file; revised following
referees' comments; to appear in Physical Review Letters | null | 10.1103/PhysRevLett.83.3758 | UQCMP-99-1 | quant-ph | null | The integral of the Wigner function over a subregion of the phase-space of a
quantum system may be less than zero or greater than one. It is shown that for
systems with one degree of freedom, the problem of determining the best
possible upper and lower bounds on such an integral, over all possible states,
reduces to the problem of finding the greatest and least eigenvalues of an
hermitian operator corresponding to the subregion. The problem is solved
exactly in the case of an arbitrary elliptical region. These bounds provide
checks on experimentally measured quasiprobability distributions.
| [
{
"version": "v1",
"created": "Fri, 28 May 1999 00:40:32 GMT"
},
{
"version": "v2",
"created": "Sat, 9 Oct 1999 07:14:33 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Bracken",
"A. J.",
"",
"ASI, TU-Clausthal"
],
[
"Doebner",
"H. -D.",
"",
"ASI, TU-Clausthal"
],
[
"Wood",
"J. G.",
"",
"University of Queensland"
]
] |
quant-ph/9905098 | Sandhya S. N. | S N Sandhya | Resonance flourescence in atomic coherent systems: spectral features | 15 pages, RevTex including postscript figures. Corrected typos | null | null | MRI-PHY/P990516 | quant-ph | null | We study resonance flourescence in a four level ladder system and illustrate
some novel features due to quantum interference and atomic coherence effects.
We find that under three photon resonant conditions, in some region of the
parameter space of the rabi frequencies $\Omega_1,\Omega_2,\Omega_3$, emission
is dominantly by the level 4 at the line center even though there is an almost
equal distribution of populations in all the levels. As one increases
$\Omega_3$ with $\Omega_1 and \Omega_2$ held fixed, the four level system
'dynamically collapses' to a two level system. The steady state populations and
the the resonance flourescence from all the levels provide adequate evidence to
this effect.
| [
{
"version": "v1",
"created": "Fri, 28 May 1999 09:53:57 GMT"
},
{
"version": "v2",
"created": "Fri, 4 Jun 1999 06:21:24 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Sandhya",
"S N",
""
]
] |
quant-ph/9905099 | J. Mark Ettinger | J. Mark Ettinger (LANL), Peter Hoyer (BRICS) | Quantum State Detection Via Elimination | 8 pages, no figures | null | null | LAUR-992667 | quant-ph | null | We present the view of quantum algorithms as a search-theoretic problem. We
show that the Fourier transform, used to solve the Abelian hidden subgroup
problem, is an example of an efficient elimination observable which eliminates
a constant fraction of the candidate secret states with high probability.
Finally, we show that elimination observables do not always exist by
considering the geometry of the hidden subgroup states of the dihedral group
D_N.
| [
{
"version": "v1",
"created": "Fri, 28 May 1999 12:16:51 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Ettinger",
"J. Mark",
"",
"LANL"
],
[
"Hoyer",
"Peter",
"",
"BRICS"
]
] |
quant-ph/9905100 | S. Seshadri | S. Seshadri, V. Balakrishnan and S. Lakshmibala (Department of
Physics, IIT-Madras, India) | Ladder operators for isospectral oscillators | 13 pages | J.Math.Phys. 39 (1998) 838-847 | 10.1063/1.532355 | null | quant-ph | null | We present, for the isospectral family of oscillator Hamiltonians, a
systematic procedure for constructing raising and lowering operators satisfying
any prescribed `distorted' Heisenberg algebra (including the
$q$-generalization). This is done by means of an operator transformation
implemented by a shift operator. The latter is obtained by solving an
appropriate partial isometry condition in the Hilbert space. Formal
representations of the non-local operators concerned are given in terms of
pseudo-differential operators. Using the new annihilation operators, new
classes of coherent states are constructed for isospectral oscillator
Hamiltonians. The corresponding Fock-Bargmann representations are also
considered, with specific reference to the order of the entire function family
in each case.
| [
{
"version": "v1",
"created": "Mon, 31 May 1999 08:45:09 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Seshadri",
"S.",
"",
"Department of\n Physics, IIT-Madras, India"
],
[
"Balakrishnan",
"V.",
"",
"Department of\n Physics, IIT-Madras, India"
],
[
"Lakshmibala",
"S.",
"",
"Department of\n Physics, IIT-Madras, India"
]
] |
quant-ph/9905101 | S. Seshadri | S. Seshadri, S. Lakshmibala and V. Balakrishnan (Department of
Physics, IIT-Madras, India) | Geometric phases for generalized squeezed coherent states | 15 pages | Phys.Rev.A55:869-875,1997 | 10.1103/PhysRevA.55.869 | null | quant-ph | null | A simple technique is used to obtain a general formula for the Berry phase
(and the corresponding Hannay angle) for an arbitrary Hamiltonian with an
equally-spaced spectrum and appropriate ladder operators connecting the
eigenstates. The formalism is first applied to a general deformation of the
oscillator involving both squeezing and displacement. Earlier results are shown
to emerge as special cases. The analysis is then extended to multiphoton
squeezed coherent states and the corresponding anholonomies deduced.
| [
{
"version": "v1",
"created": "Mon, 31 May 1999 12:21:46 GMT"
}
] | 2008-12-18T00:00:00 | [
[
"Seshadri",
"S.",
"",
"Department of\n Physics, IIT-Madras, India"
],
[
"Lakshmibala",
"S.",
"",
"Department of\n Physics, IIT-Madras, India"
],
[
"Balakrishnan",
"V.",
"",
"Department of\n Physics, IIT-Madras, India"
]
] |
quant-ph/9905102 | Volodymyr Tkachuk | V. M. Tkachuk, P. Roy | Supersymmetry of a spin 1/2 particle on the real line | 8 pages, LaTeX, no figure | Phys.Lett. A263 (1999) 245-249 | 10.1016/S0375-9601(99)00776-8 | null | quant-ph | null | We study one dimensional supersymmetric (SUSY) quantum mechanics of a spin
1/2 particle moving in a rotating magnetic field and scalar potential. We also
discuss SUSY breaking and it is shown that SUSY breaking essentially depends on
the strength and period of the magnetic field. For a purely rotating magnetic
field the eigenvalue problem is solved exactly and two band energy spectrum is
found.
| [
{
"version": "v1",
"created": "Mon, 31 May 1999 12:07:13 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Tkachuk",
"V. M.",
""
],
[
"Roy",
"P.",
""
]
] |
quant-ph/9906001 | Stefan Scheel | S. Scheel and D.-G. Welsch | QED in the Presence of Arbitrary Kramers-Kronig Dielectric Media | 4 pages, LaTeX, contribution to the Sixth International Conference on
Squeezed states and Uncertainty relations ICSSUR VI, Naples 24-29 May 1999 | null | null | null | quant-ph | null | The phenomenological Maxwell field is quantized for arbitrarily space- and
frequency-dependent complex permittivity. The formalism takes account of the
Kramers--Kronig relation and the dissipation-fluctuation theorem and yields the
fundamental equal-time commutation relations of QED. Applications to the
quantum-state transformation at absorbing and amplifying four-port devices and
to the spontaneous decay of an excited atom in the presence of absorbing
dielectric bodies are discussed.
| [
{
"version": "v1",
"created": "Tue, 1 Jun 1999 09:03:48 GMT"
},
{
"version": "v2",
"created": "Fri, 16 Jul 1999 09:29:15 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Scheel",
"S.",
""
],
[
"Welsch",
"D. -G.",
""
]
] |
quant-ph/9906002 | Habatwa Vincent Mweene | Habatwa Vincent Mweene (Physics Department, University of Zambia) | Generalized Spin-1/2 Operators and Their Eigenvectors | LaTeX, 10 pages.Replaced after thorough revision of notation and
improvement to some sections | null | null | UNZAPHYS-002 | quant-ph | null | Recently, we have shown how the interpretation of quantum mechanics due to
Lande' can be used to derive from first principles generalized formulas for the
operators and some eigenvectors for spin 1/2 Though we gave the operators for
all the components of the spin, we did not give the eigenvectors of the
operators for the x and y components of the spin. We now give these vectors. In
addition, we present a new and simple method of deriving the operators for the
x and y components of the spin as well as their vectors from those for the z
component. We give a general proof that the operator for the square of the spin
is the unit matrix multiplied by the value of the square of the spin.
| [
{
"version": "v1",
"created": "Tue, 1 Jun 1999 10:12:41 GMT"
},
{
"version": "v2",
"created": "Sat, 1 Jul 2000 00:36:27 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Mweene",
"Habatwa Vincent",
"",
"Physics Department, University of Zambia"
]
] |
quant-ph/9906003 | Avi Marhavka | A. Marchewka, Z. Schuss | Feynman Integral Approach to Absorption in Quantum Mechanics | 26 pages, latex2e | null | null | TAUP 2571-99 | quant-ph | null | We propose a formulation of an absorbing boundary for a quantum particle. The
formulation is based on a Feynman-type integral over trajectories that are
confined by the absorbing boundary. Trajectories that reach the absorbing wall
are instantaneously terminated and their probability is discounted from the
population of the surviving trajectories. This gives rise to a unidirectional
absorption current at the boundary. We calculate the survival probability as a
function of time. Several modes of absorption are derived from our formalism:
total absorption, absorption that depends on energy levels, and absorption of
non-interacting particles. Several applications are given: the slit experiment
with an absorbing screen and with absorbing lateral walls, and one dimensional
particle between two absorbing walls. The survival probability of a particle
between absorbing walls exhibits decay with beats.
| [
{
"version": "v1",
"created": "Tue, 1 Jun 1999 12:03:17 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Marchewka",
"A.",
""
],
[
"Schuss",
"Z.",
""
]
] |
quant-ph/9906004 | Ioan Sturzu | Ioan Sturzu (Physics Department, ''Transilvania'' University, Brasov,
Romania) | Unsharp measurements and the conceptual problems of Quantum Theory | 7 pages | null | null | null | quant-ph | null | The paper emphasis the role of unsharpness in the body of Quantum Theory and
the relations to the conceptual problems of the Theory. Key words: quantum
measurement, unsharpness, effect, positive operator-valued measure
| [
{
"version": "v1",
"created": "Tue, 1 Jun 1999 14:31:17 GMT"
},
{
"version": "v2",
"created": "Sun, 6 Jun 1999 23:58:31 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Sturzu",
"Ioan",
"",
"Physics Department, ''Transilvania'' University, Brasov,\n Romania"
]
] |
quant-ph/9906005 | Ian C. Percival | Ian C. Percival | Quantum measurement breaks Lorentz symmetry | 48 pages, 18 figures, mostly at the end. LaTeX | null | null | QMW-TH-99-07 | quant-ph gr-qc | null | Traditionally causes come before effects, but according to modern physics
things aren't that simple. Special relativity shows that `before' and `after'
are relative, and quantum measurement is even more subtle. Since the
nonlocality of Bell's theorem, it has been known that quantum measurement has
an uneasy relation with special relativity, described by Shimony as `peaceful
coexistence'. Hardy's theorem says that quantum measurement requires a
preferred Lorentz frame. The original proofs of the theorem depended on there
being no backward causality, even at the quantum level. In quant-ph/9803044
this condition was removed. It was only required that systems with classical
inputs and outputs had no causal loops. Here the conditions are weakened
further: there should be no forbidden causal loops as defined in the text. The
theory depends on a transfer function analysis, which is introduced in detail
before application to specific systems.
| [
{
"version": "v1",
"created": "Tue, 1 Jun 1999 14:23:09 GMT"
},
{
"version": "v2",
"created": "Wed, 2 Jun 1999 13:15:47 GMT"
}
] | 2009-09-25T00:00:00 | [
[
"Percival",
"Ian C.",
""
]
] |
quant-ph/9906006 | Adrian Kent | Adrian Kent (Centre for Quantum Computation, Oxford University and
DAMTP, University of Cambridge) | Non-Contextual Hidden Variables and Physical Measurements | Typo corrected. Final version: to appear in Phys. Rev. Lett | Phys.Rev.Lett.83:3755-3757,1999 | 10.1103/PhysRevLett.83.3755 | DAMTP-1999-76 | quant-ph | null | For a hidden variable theory to be indistinguishable from quantum theory for
finite precision measurements, it is enough that its predictions agree for some
measurement within the range of precision. Meyer has recently pointed out that
the Kochen-Specker theorem, which demonstrates the impossibility of a
deterministic hidden variable description of ideal spin measurements on a spin
1 particle, can thus be effectively nullified if only finite precision
measurements are considered. We generalise this result: it is possible to
ascribe consistent outcomes to a dense subset of the set of projection valued
measurements, or to a dense subset of the set of positive operator valued
measurements, on any finite dimensional system. Hence no Kochen-Specker like
contradiction can rule out hidden variable theories indistinguishable from
quantum theory by finite precision measurements in either class.
| [
{
"version": "v1",
"created": "Tue, 1 Jun 1999 17:28:58 GMT"
},
{
"version": "v2",
"created": "Tue, 22 Jun 1999 13:24:01 GMT"
},
{
"version": "v3",
"created": "Fri, 17 Sep 1999 12:31:59 GMT"
}
] | 2009-01-23T00:00:00 | [
[
"Kent",
"Adrian",
"",
"Centre for Quantum Computation, Oxford University and\n DAMTP, University of Cambridge"
]
] |
quant-ph/9906007 | David Deutsch | David Deutsch and Patrick Hayden | Information Flow in Entangled Quantum Systems | PostScript version now available:
http://www.qubit.org/people/patrickh/Papers/InformationFlow.ps | Proc. R. Soc. Lond. A 456(1999):1759-1774, 2000. | 10.1098/rspa.2000.0585 | null | quant-ph | null | All information in quantum systems is, notwithstanding Bell's theorem,
localised. Measuring or otherwise interacting with a quantum system S has no
effect on distant systems from which S is dynamically isolated, even if they
are entangled with S. Using the Heisenberg picture to analyse quantum
information processing makes this locality explicit, and reveals that under
some circumstances (in particular, in Einstein-Podolski-Rosen experiments and
in quantum teleportation) quantum information is transmitted through
'classical' (i.e. decoherent) information channels.
| [
{
"version": "v1",
"created": "Tue, 1 Jun 1999 18:06:54 GMT"
},
{
"version": "v2",
"created": "Fri, 4 Jun 1999 15:29:03 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Deutsch",
"David",
""
],
[
"Hayden",
"Patrick",
""
]
] |
quant-ph/9906008 | Noah Linden | Noah Linden and Sandu Popescu | Good dynamics versus bad kinematics. Is entanglement needed for quantum
computation? | 4 pages, Revtex Revised, error-corrected, version; conclusions
unchanged | Phys.Rev.Lett. 87 (2001) 047901 | 10.1103/PhysRevLett.87.047901 | null | quant-ph | null | We consider quantum computing with pseudo-pure states. This framework arises
in certain implementations of quantum computing using NMR. We analyze quantum
computational protocols which aim to solve exponential classical problems with
polynomial resources and ask whether or not entanglement of the pseudo-pure
states is needed to achieve this aim. We show that for a large class of such
protocols, including Shor's factorization, entanglement is necessary. We also
show that achieving entanglement is not sufficient: if the noise in the state
is sufficiently large, exponential resources are needed even if entanglement is
present.
| [
{
"version": "v1",
"created": "Tue, 1 Jun 1999 20:57:36 GMT"
},
{
"version": "v2",
"created": "Thu, 3 Jun 1999 16:20:40 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Linden",
"Noah",
""
],
[
"Popescu",
"Sandu",
""
]
] |
quant-ph/9906009 | Jochen Dittmann | J. Dittmann | On the Curvature of Monotone Metrics and a Conjecture Concerning the
Kubo-Mori Metric | 20 pages, 4 figures | null | null | null | quant-ph math-ph math.DG math.MP | null | It is the aim of this article to determine curvature quantities of an
arbitrary Riemannian monotone metric on the space of positive matrices resp.
nonsingular density matrices. Special interest is focused on the scalar
curvature due to its expected quantum statistical meaning. The scalar curvature
is explained in more detail for three examples, the Bures metric, the largest
monotone metric and the Kubo-Mori metric. In particular, we show an important
conjecture of Petz concerning the Kubo-Mori metric up to a formal proof of the
concavity of a certain function on R_+^3. This concavity seems to be
numerically evident. The conjecture of Petz asserts that the scalar curvature
of the Kubo-Mori metric increases if one goes to more mixed states.
| [
{
"version": "v1",
"created": "Wed, 2 Jun 1999 12:25:40 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Dittmann",
"J.",
""
]
] |
quant-ph/9906010 | Vladimir Manko | Margarita A. Man'ko | Quantum Tomography Approach in Signal Analysis | LATEX, 5pages, to be published in the Proceedings of the Sixth
International Conference on Squeezed States and Uncertainty Relations
(Naples, Italy, May 1999) in NASA Conference Series | null | null | null | quant-ph | null | Some properties of the fractional Fourier transform, which is used in
information processing, are presented in connection with the tomography
transform of optical signals. Relation of the Green function of the quantum
harmonic oscillator to the fractional Fourier transform is elucidated.
| [
{
"version": "v1",
"created": "Wed, 2 Jun 1999 16:13:07 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Man'ko",
"Margarita A.",
""
]
] |
quant-ph/9906011 | Bieberich | Erhard Bieberich | Non-local quantum evolution of entangled ensemble states in neural nets
and its significance for brain function and a theory of consciousness | 15 pages, no figures The original version was thoroughly revised with
focus on clarity of "language" (quantum physics and neuroscience) used. The
amended version contains a new section with reference to recent publications
on quantum effects in the brain | null | null | null | quant-ph | null | Current quantum theories of consciousness suggest a configuration space of an
entangled ensemble state as global work space for conscious experience. This
study will describe a procedure for adjustment of the singlet evolution of a
quantum computation to a classical signal input by action potentials. The
computational output of an entangled state in a single neuron will be selected
in a network environment by "survival of the fittest" coupling with other
neurons. Darwinian evolution of this coupling will result in a binding of
action potentials to a convoluted orbit of phase-locked oscillations with
harmonic, m-adic, or fractal periodicity. Progressive integration of signal
inputs will evolve a present memory space independent from the history of
construction. Implications for mental processes, e.g., associative memory,
creativity, and consciousness will be discussed. A model for the generation of
quantum coherence in a single neuron will be suggested.
| [
{
"version": "v1",
"created": "Wed, 2 Jun 1999 17:44:10 GMT"
},
{
"version": "v2",
"created": "Mon, 26 Jul 1999 16:37:08 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bieberich",
"Erhard",
""
]
] |
quant-ph/9906012 | Serban Misicu | S. Misicu | Quantum tunneling with dissipation in smoothly joined parabolic
potential | 8 pages, 9 figures | null | null | null | quant-ph | null | This paper is devoted to the study of quantum dissipation in cluster decay
phenomena in the frame of the Lindblad approach to quantum open systems. The
tunneling of a metastable state across a piecewise quadratic potential is
envisaged for two cases : one and two harmonic wells smoothly joined to an
inverted parabola which simulates the barrier. The width and depth of the
second harmonic oscillator well was varied over a wide range of values in order
to encompass particular cases of tunneling such as the double well potential
and the cluster decay. The evolution of the averages and covariances of the
quantum sub-system is studied in both under- and overdamped regimes. For a
gaussian intial wave-packet we compute the tunneling probability for different
values of the friction coefficient and fixed values of the diffusion
coefficients.
| [
{
"version": "v1",
"created": "Thu, 3 Jun 1999 06:45:17 GMT"
}
] | 2016-09-08T00:00:00 | [
[
"Misicu",
"S.",
""
]
] |
quant-ph/9906013 | Barry C. Sanders | Y. Ben-Aryeh, A. Mann and B. C. Sanders | Empirical State Determination of Entangled Two-Level Systems and its
Relation to Information Theory | null | Found.Phys. 29 (1999) 1963-1975 | null | null | quant-ph | null | Theoretical methods for empirical state determination of entangled two-level
systems are analyzed in relation to information theory. We show that hidden
variable theories would lead to a Shannon index of correlation between the
entangled subsystems which is larger that that predicted by quantum mechanics.
Canonical representations which have maximal correlations are treated by the
use of Schmidt decomposition of the entangled states, including especially the
Bohm singlet state and the GHZ entangled states. We show that quantum mechanics
does not violate locality, but does violate realism.
| [
{
"version": "v1",
"created": "Thu, 3 Jun 1999 11:34:51 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Ben-Aryeh",
"Y.",
""
],
[
"Mann",
"A.",
""
],
[
"Sanders",
"B. C.",
""
]
] |
quant-ph/9906014 | Sharon Jensen | H. Pierre Noyes | Science and Paranormal Phenomena | LaTex, 10 pages | null | null | SLAC-PUB-8151 | quant-ph | null | In order to ground my approach to the study of paranormal phenomena, I first
explain my operational approach to physics, and to the ``historical'' sciences
of cosmic, biological, human, social and political evolution. I then indicate
why I believe that ``paranormal phenomena'' might --- but need not --- fit into
this framework. I endorse the need for a new theoretical framework for the
investigation of this field presented by Etter and Shoup at this meeting. I
close with a short discussion of Ted Bastin's contention that paranormal
phenomena should be {\it defined} as contradicting physics.
| [
{
"version": "v1",
"created": "Thu, 3 Jun 1999 18:05:40 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Noyes",
"H. Pierre",
""
]
] |
quant-ph/9906015 | David Deutsch | David Deutsch | Quantum Theory of Probability and Decisions | null | null | 10.1098/rspa.1999.0443 | null | quant-ph | null | The probabilistic predictions of quantum theory are conventionally obtained
from a special probabilistic axiom. But that is unnecessary because all the
practical consequences of such predictions follow from the remaining,
non-probabilistic, axioms of quantum theory, together with the
non-probabilistic part of classical decision theory.
| [
{
"version": "v1",
"created": "Fri, 4 Jun 1999 00:16:28 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Deutsch",
"David",
""
]
] |
quant-ph/9906016 | Jonathan P. Dowling | Jonathan P. Dowling (1), Colin P. Williams (1), and J. D. Franson (2)
((1) Jet Propulsion Laboratory, California Institute of Technology; (2)
Applied Physics Laboratory, Johns Hopkins University) | Maxwell Duality, Lorentz Invariance, and Topological Phase | 10 pages, 2 figures | Phys.Rev.Lett. 83 (1999) 2486-2489 | 10.1103/PhysRevLett.83.2486 | null | quant-ph | null | We discuss the Maxwell electromagnetic duality relations between the
Aharonov-Bohm, Aharonov-Casher, and He-McKellar-Wilkens topological phases,
which allows a unified description of all three phenomena. We also elucidate
Lorentz transformations that allow these effects to be understood in an
intuitive fashion in the rest frame of the moving quantum particle. Finally, we
propose two experimental schemes for measuring the He-McKellar-Wilkens phase.
| [
{
"version": "v1",
"created": "Fri, 4 Jun 1999 18:33:30 GMT"
},
{
"version": "v2",
"created": "Thu, 10 Jun 1999 20:00:01 GMT"
},
{
"version": "v3",
"created": "Fri, 6 Aug 1999 01:17:51 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Dowling",
"Jonathan P.",
""
],
[
"Williams",
"Colin P.",
""
],
[
"Franson",
"J. D.",
""
]
] |
quant-ph/9906017 | Jonathan P. Dowling | Jonathan P. Dowling (Jet Propulsion Laboratory, California Institute
of Technology) | Dipole Emission In Finite Photonic Band-Gap Structures: an Exactly
Solvable One-Dimensional Model | 23 pages, 7 figures | null | 10.1109/50.803005 | null | quant-ph | null | I consider an exact model of atomic spontaneous dipole emission and classical
dipole radiation in a finite photonic band-gap structure. The full 3D or 2D
problem is reduced to a finite 1D model, and then this is solved for
analytically using algebraic matrix transfer techniques. The results give
insight to the electromagnetic emission process in periodic dielectrics,
quantitative predictions for emission in 1D dielectric stacks, and qualitative
formulas for the 2D and 3D problem.
| [
{
"version": "v1",
"created": "Fri, 4 Jun 1999 01:52:55 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Dowling",
"Jonathan P.",
"",
"Jet Propulsion Laboratory, California Institute\n of Technology"
]
] |
quant-ph/9906018 | Molotkov S. | S.N.Molotkov and S.S.Nazin (Institute of Solid State Physics, Russian
Academy of Sciences) | On the Teleportation of Continuous Variable | 13 pages, no figures. To be published in JETP | J.Exp.Theor.Phys. 89 (1999) 413-420; Zh.Eksp.Teor.Fiz. 116 (1999)
777-792 | 10.1134/1.558998 | null | quant-ph | null | The measurement procedures used in quantum teleportation are analyzed from
the viewpoint of the general theory of quantum-mechanical measurements. It is
shown that to find the teleported state one should only know the identity
resolution (positive operator-valued measure) generated by the corresponding
instrument (quantum operation describing the system state change caused by the
measurement) rather than the instrument itself. A quantum teleportation
protocol based on a measurement associated with a non-orthogonal identity
resolution is proposed for a system with non-degenerate continuous spectrum.
| [
{
"version": "v1",
"created": "Fri, 4 Jun 1999 10:02:51 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Molotkov",
"S. N.",
"",
"Institute of Solid State Physics, Russian\n Academy of Sciences"
],
[
"Nazin",
"S. S.",
"",
"Institute of Solid State Physics, Russian\n Academy of Sciences"
]
] |
quant-ph/9906019 | Arturo Lezama | A.M. Akulshin S. Barreiro A. Lezama | Steep anomalous dispersion in coherently prepared Rb vapor | 4 pages, 4 figures | Phys.Rev.Lett.83:4277,1999 | 10.1103/PhysRevLett.83.4277 | null | quant-ph | null | Steep dispersion of opposite signs in driven degenerate two-level atomic
transitions have been predicted and observed on the D2 line of 87Rb in an
optically thin vapor cell. The intensity dependence of the anomalous dispersion
has been studied. The maximum observed value of anomalous dispersion [dn/dnu ~=
-6x10^{-11}Hz^{-1}] corresponds to anegative group velocity V_g ~= -c/23000.
| [
{
"version": "v1",
"created": "Fri, 4 Jun 1999 15:32:30 GMT"
}
] | 2009-01-23T00:00:00 | [
[
"Lezama",
"A. M. Akulshin S. Barreiro A.",
""
]
] |
quant-ph/9906020 | Gui Lu Long | Gui Lu Long, Yan Song Li, Wei Lin Zhang and Li Niu | Phase matching in quantum searching | 13 pages, 7 figures | Phys.Lett. A262 (1999) 27-34 | 10.1016/S0375-9601(99)00631-3 | null | quant-ph | null | Each iteration in Grover's original quantum search algorithm contains 4
steps: two Hadamard-Walsh transformations and two amplitudes inversions. When
the inversion of the marked state is replaced by arbitrary phase rotation
\theta and the inversion for the prepared state |\gamma> is replaced by
rotation through \phi, we found that these phase rotations must satisfy a
matching condition \theta=\phi. Approximate formula for the amplitude of the
marked state after an arbitrary number of iterations are also derived. We give
also a simple explanation of the phase matching requirement.
| [
{
"version": "v1",
"created": "Sat, 5 Jun 1999 09:32:50 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Long",
"Gui Lu",
""
],
[
"Li",
"Yan Song",
""
],
[
"Zhang",
"Wei Lin",
""
],
[
"Niu",
"Li",
""
]
] |
quant-ph/9906021 | Peter van Loock | P. van Loock and Samuel L. Braunstein | Multipartite entanglement for continuous variables: A quantum
teleportation network | 4 pages, 2 figures, published version, paper shorter, title longer | Phys. Rev. Lett. 84, 3482 (2000) | 10.1103/PhysRevLett.84.3482 | null | quant-ph | null | We show that {\it one} single-mode squeezed state distributed among $N$
parties using linear optics suffices to produce a truly $N$-partite entangled
state for any nonzero squeezing and arbitrarily many parties. From this
$N$-partite entangled state, via quadrature measurements of $N-2$ modes,
bipartite entanglement between any two of the $N$ parties can be `distilled',
which enables quantum teleportation with an experimentally determinable
fidelity better than could be achieved in any classical scheme.
| [
{
"version": "v1",
"created": "Sun, 6 Jun 1999 14:00:43 GMT"
},
{
"version": "v2",
"created": "Mon, 19 Jun 2000 15:59:39 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"van Loock",
"P.",
""
],
[
"Braunstein",
"Samuel L.",
""
]
] |
quant-ph/9906022 | Irina Aref'eva | I.Ya. Aref'eva and I.V. Volovich | Quantum Decoherence and Higher Order Corrections to the Large Time
Exponential Behaviour | 30 pages, 9 figures | null | null | SMI-16-99 | quant-ph cond-mat.stat-mech hep-th | null | There exists the well known approximate expression describing the large time
behaviour of matrix elements of the evolution operator in quantum theory:
<U(t)>=exp(at)+... This expression plays the crucial role in considerations of
problems of quantum decoherence, radiation, decay, scattering theory,
stochastic limit, derivation of master and kinetic equations etc. This
expression was obtained in the Weisskopf-Wigner approximation and in the van
Hove (stochastic) limit. We derive the exact general formula which includes the
higher order corrections to the above approximate expression:
<U(t)>=exp(At+B+C(t)). The constants A and B and the oscillating function C(t)
are computed in perturbation theory. The method of perturbation of spectra and
renormalized wave operators is used. The formula is valid for a general class
of Hamiltonians used in statistical physics and quantum field theory.
| [
{
"version": "v1",
"created": "Sun, 6 Jun 1999 19:59:31 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Aref'eva",
"I. Ya.",
""
],
[
"Volovich",
"I. V.",
""
]
] |
quant-ph/9906023 | Asher Peres | Asher Peres | Classical interventions in quantum systems. I. The measuring process | Final version, 14 pages LaTeX | Physical Review A 61 (2000) 022116 | 10.1103/PhysRevA.61.022116 | null | quant-ph | null | The measuring process is an external intervention in the dynamics of a
quantum system. It involves a unitary interaction of that system with a
measuring apparatus, a further interaction of both with an unknown environment
causing decoherence, and then the deletion of a subsystem. This description of
the measuring process is a substantial generalization of current models in
quantum measurement theory. In particular, no ancilla is needed. The final
result is represented by a completely positive map of the quantum state $\rho$
(possibly with a change of the dimensions of $\rho$). A continuous limit of the
above process leads to Lindblad's equation for the quantum dynamical semigroup.
| [
{
"version": "v1",
"created": "Mon, 7 Jun 1999 14:42:05 GMT"
},
{
"version": "v2",
"created": "Fri, 11 Jun 1999 07:39:02 GMT"
},
{
"version": "v3",
"created": "Mon, 7 Feb 2000 14:21:53 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Peres",
"Asher",
""
]
] |
quant-ph/9906024 | B. Kappler | H. P. Breuer, B. Kappler and F. Petruccione | Stochastic wave function method for non-Markovian quantum master
equations | RevTex, 14 pages, 9 figures, uses multicol | Phys.Rev. A59 (1999) 1633-1643 | 10.1103/PhysRevA.59.1633 | null | quant-ph | null | A generalization of the stochastic wave function method to quantum master
equations which are not in Lindblad form is developed. The proposed stochastic
unravelling is based on a description of the reduced system in a doubled
Hilbert space and it is shown, that this method is capable of simulating
quantum master equations with negative transition rates. Non-Markovian effects
in the reduced systems dynamics can be treated within this approach by
employing the time-convolutionless projection operator technique. This ansatz
yields a systematic perturbative expansion of the reduced systems dynamics in
the coupling strength. Several examples such as the damped Jaynes Cummings
model and the spontaneous decay of a two-level system into a photonic band gap
are discussed. The power as well as the limitations of the method are
demonstrated.
| [
{
"version": "v1",
"created": "Mon, 7 Jun 1999 09:43:20 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Breuer",
"H. P.",
""
],
[
"Kappler",
"B.",
""
],
[
"Petruccione",
"F.",
""
]
] |
quant-ph/9906025 | Todd A. Brun | Todd A. Brun (Carnegie Mellon University), Hailin Wang (University of
Oregon) | Coupling nanocrystals to a high-$Q$ silica microsphere: entanglement in
quantum dots via photon exchange | 5 pages RevTeX 3.0 + 3 figures (encapsulated postscript). Submitted
to Physical Review Letters | Phys.Rev.A61:032307,2000 | 10.1103/PhysRevA.61.032307 | null | quant-ph cond-mat | null | Coupling nanocrystals (quantum dots) to a high-$Q$ whispering gallery mode
(WGM) of a silica microsphere, can produce a strong coherent interaction
between the WGM and the electronic states of the dots. Shifting the resonance
frequencies of the dots, for instance by placing the entire system in an
electric potential, then allows this interaction to be controlled, permitting
entangling interactions between different dots. Thus, this system could
potentially be used to implement a quantum computer.
| [
{
"version": "v1",
"created": "Tue, 8 Jun 1999 16:19:39 GMT"
}
] | 2008-12-18T00:00:00 | [
[
"Brun",
"Todd A.",
"",
"Carnegie Mellon University"
],
[
"Wang",
"Hailin",
"",
"University of\n Oregon"
]
] |
quant-ph/9906026 | Wei-Mou Zheng | Wei-Mou Zheng | Nonperiodic Orbit Sums in Weyl's Expansion for Billiards | 8 pages, 2 figures | Phys.Rev.E60:2845-2850,1999 | 10.1103/PhysRevE.60.2845 | ASITP-990428 | quant-ph | null | Weyl's expansion for the asymptotic mode density of billiards consists of the
area, length, curvature and corner terms. The area term has been associated
with the so-called zero-length orbits. Here closed nonperiodic paths
corresponding to the length and corner terms are constructed.
| [
{
"version": "v1",
"created": "Wed, 9 Jun 1999 00:38:18 GMT"
}
] | 2008-12-18T00:00:00 | [
[
"Zheng",
"Wei-Mou",
""
]
] |
quant-ph/9906027 | Arvind | Kavita Dorai (IISc Bangalore) and Arvind (GNDU Amritsar) and Anil
Kumar(IISc Bangalore) | Implementing quantum logic operations, pseudo-pure states and the
Deutsch-Jozsa algorithm using non-commuting selective pulses in NMR | Final version to Appear in Phys. Rev. A April 2000 | Phys.Rev.A61:042306,2000 | 10.1103/PhysRevA.61.042306 | null | quant-ph | null | We demonstrate experimentally the usefulness of selective pulses in NMR to
perform quantum computation. Three different techniques based on selective
pulse excitations have been proposed to prepare a spin system in a pseudo-pure
state. We describe the design of novel ``portmanteau'' gates using the
selective manipulation of level populations. A selective pulse implementation
of the Deutsch-Jozsa algorithm for a two-qubit and a three-qubit quantum
computer is demonstrated.
| [
{
"version": "v1",
"created": "Wed, 9 Jun 1999 06:48:48 GMT"
},
{
"version": "v2",
"created": "Sat, 5 Feb 2000 11:39:59 GMT"
}
] | 2008-12-18T00:00:00 | [
[
"Dorai",
"Kavita",
"",
"IISc Bangalore"
],
[
"Arvind",
"",
"",
"GNDU Amritsar"
],
[
"Kumar",
"Anil",
"",
"IISc Bangalore"
]
] |
quant-ph/9906028 | Bhabani Prasad Mandal | Bhabani Prasad Mandal (Saha Institute of Nuclear Physics) | Path Integral Solution to Non-central Potential | Latex, 14 pages, No figs. To appear in IJMPA,1999 | Int.J.Mod.Phys. A15 (2000) 1225-1234 | null | null | quant-ph hep-th | null | We have studied the path integral solution of a system of particle moving in
certain class of non-central potential without using Kustannheimo-Stiefel
transformation. The Hamiltonian of the system has been converted to a separable
Hamiltonian of Liouville type in parabolic coordinates and has further reduced
to a Hamiltonian corresponding to two 2- dimensional simple harmonic
oscillators. The energy spectrum for this system is calculated analytically.
Hartmann ring-shaped potential and compound Coulomb plus Aharanov- Bohm
potential have also been studied as special cases.
| [
{
"version": "v1",
"created": "Wed, 9 Jun 1999 11:19:53 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Mandal",
"Bhabani Prasad",
"",
"Saha Institute of Nuclear Physics"
]
] |
quant-ph/9906029 | Miloslav Znojil | Miloslav Znojil | Non-Hermitian matrix description of the PT symmetric anharmonic
oscillators | 18 pages, latex, no figures, thoroughly revised (incl. title), J.
Phys. A: Math. Gen., to appear | J.Phys.A32:7419-7428,1999 | 10.1088/0305-4470/32/42/313 | null | quant-ph | null | Schroedinger equation H \psi=E \psi with PT - symmetric differential operator
H=H(x) = p^2 + a x^4 + i \beta x^3 +c x^2+i \delta x = H^*(-x) on
L_2(-\infty,\infty) is re-arranged as a linear algebraic diagonalization at
a>0. The proof of this non-variational construction is given. Our Taylor series
form of \psi complements and completes the recent terminating solutions as
obtained for certain couplings \delta at the less common negative a.
| [
{
"version": "v1",
"created": "Wed, 9 Jun 1999 11:37:40 GMT"
},
{
"version": "v2",
"created": "Tue, 7 Sep 1999 09:39:52 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Znojil",
"Miloslav",
""
]
] |
quant-ph/9906030 | Benni Reznik | Yakir Aharonov and Benni Reznik | ``Weighing'' a closed system and the time-energy uncertainty principle | 8 pages | Phys.Rev.Lett.84:1368-1370,2000 | 10.1103/PhysRevLett.84.1368 | null | quant-ph gr-qc | null | A gedanken-experiment is proposed for `weighing'' the total mass of a closed
system from within the system. We prove that for an internal observer the time
$\tau$, required to measure the total energy with accuracy $\Delta E$, is
bounded according to $\tau \Delta E >\hbar $. This time-energy uncertainty
principle for a closed system follows from the measurement back-reaction on the
system. We generally examine what other conserved observables are in principle
measurable within a closed system and what are the corresponding uncertainty
relations.
| [
{
"version": "v1",
"created": "Wed, 9 Jun 1999 13:35:19 GMT"
}
] | 2009-01-23T00:00:00 | [
[
"Aharonov",
"Yakir",
""
],
[
"Reznik",
"Benni",
""
]
] |
quant-ph/9906031 | Stefano Mancini | S. Mancini | Quantum dynamics of a damped deformed oscillator | LaTeX file, 6 pages | Phys.Scripta 59 (1999) 195 | 10.1238/Physica.Regular.059a00195 | null | quant-ph | null | The interaction of a quantum deformed oscillator with the environment is
studied deriving a master equation whose form strongly depends on the type of
deformation.
| [
{
"version": "v1",
"created": "Wed, 9 Jun 1999 14:12:15 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Mancini",
"S.",
""
]
] |
quant-ph/9906032 | Stefano Mancini | S. Mancini | Stochastic control of quantum dynamics for a single trapped system | LaTeX file, 7 pages, contribution to proceedings of 6th
central-european workshop on quantum optics | Acta Phys.Slov. 49 (1999) 725 | null | null | quant-ph | null | A stochastic control of the vibrational motion for a single trapped ion/atom
is proposed. It is based on the possibility to continously monitor the motion
through a light field meter. The output from the measurement process should be
then used to modify the system's dynamics.
| [
{
"version": "v1",
"created": "Wed, 9 Jun 1999 13:54:26 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Mancini",
"S.",
""
]
] |
quant-ph/9906033 | Umar Mohideen | G.L. Klimchitskaya, Anushree Roy, U. Mohideen and V.M. Mostepanenko | Complete roughness and conductivity corrections for the recent Casimir
force measurement | null | Phys.Rev.A60:3487-3495,1999 | 10.1103/PhysRevA.60.3487 | null | quant-ph | null | We consider detailed roughness and conductivity corrections to the Casimir
force in the recent Casimir force measurement employing an Atomic Force
Microscope. The roughness of the test bodies-a metal plate and a sphere- was
investigated with the Atomic Force Microscope and the Scanning Electron
Microscope respectively. It consists of separate crystals of different heights
and a stochastic background. The amplitude of roughness relative to the zero
roughness level was determined and the corrections to the Casimir force were
calculated up to the fourth order in a small parameter (which is this amplitude
divided by the distance between the two test bodies). Also the corrections due
to finite conductivity were found up to the fourth order in relative
penetration depth of electromagnetic zero point oscillations into the metal.
The theoretical result for the configuration of a sphere above a plate taking
into account both corrections is in excellent agreement with the measured
Casimir force.
| [
{
"version": "v1",
"created": "Thu, 10 Jun 1999 00:24:51 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Klimchitskaya",
"G. L.",
""
],
[
"Roy",
"Anushree",
""
],
[
"Mohideen",
"U.",
""
],
[
"Mostepanenko",
"V. M.",
""
]
] |
quant-ph/9906034 | Asher Peres | Asher Peres | Classical interventions in quantum systems. II. Relativistic invariance | Final version, 12 pages LaTeX | Physical Review A 61 (2000) 022117 | 10.1103/PhysRevA.61.022117 | null | quant-ph hep-th | null | If several interventions performed on a quantum system are localized in
mutually space-like regions, they will be recorded as a sequence of ``quantum
jumps'' in one Lorentz frame, and as a different sequence of jumps in another
Lorentz frame. Conditions are specified that must be obeyed by the various
operators involved in the calculations so that these two different sequences
lead to the same observable results. These conditions are similar to the
equal-time commutation relations in quantum field theory. They are sufficient
to prevent superluminal signaling. (The derivation of these results does not
require most of the contents of the preceding article. What is needed is
briefly summarized here, so that the present article is essentially
self-contained.)
| [
{
"version": "v1",
"created": "Thu, 10 Jun 1999 18:13:58 GMT"
},
{
"version": "v2",
"created": "Mon, 7 Feb 2000 14:22:27 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Peres",
"Asher",
""
]
] |
quant-ph/9906035 | WonYoung Hwang | WonYoung Hwang, Jeong-Young Ji, and Jongbae Hong | The Generalized Quantum Statistics | 9pages | null | null | null | quant-ph | null | The concept of wavefunction reduction should be introduced to standard
quantum mechanics in any physical processes where effective reduction of
wavefunction occurs, as well as in the measurement processes. When the overlap
is negligible, each particle obey Maxwell-Boltzmann statistics even if the
particles are in principle described by totally symmetrized wavefunction
[P.R.Holland, The Quantum Theory of Motion, Cambridge Unversity Press, 1993,
p293]. We generalize the conjecture. That is, particles obey some generalized
statistics that contains the quantum and classical statistics as special cases,
where the degree of overlapping determines the statistics that particles should
obey among continuous generalized statistics. We present an example consistent
with the conjecture.
| [
{
"version": "v1",
"created": "Fri, 11 Jun 1999 05:50:12 GMT"
},
{
"version": "v2",
"created": "Mon, 14 Jun 1999 03:34:08 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Hwang",
"WonYoung",
""
],
[
"Ji",
"Jeong-Young",
""
],
[
"Hong",
"Jongbae",
""
]
] |
quant-ph/9906036 | Kent A. Peacock | Kent A. Peacock and Brian S. Hepburn | Begging the Signalling Question: Quantum Signalling and the Dynamics of
Multiparticle Systems | 14 pages, no figures. Submitted to Proceedings of the 1999 Conference
of the Society for Exact Philosophy | null | null | UL-1999-1 | quant-ph | null | Many authors state that quantum nonlocality could not involve any
controllable superluminal transmission of momentum-energy, signals, or
information. We claim that most or all no-signalling proofs to date are
question-begging, in that they depend upon assumptions about the locality of
the measurement process that needed to be established in the first place. We
analyse no-signalling arguments by Bohm and Hiley, and Shimony, which
illustrate the problem in an especially striking way.
| [
{
"version": "v1",
"created": "Fri, 11 Jun 1999 16:40:25 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Peacock",
"Kent A.",
""
],
[
"Hepburn",
"Brian S.",
""
]
] |
quant-ph/9906037 | Yi-Xin Chen | Yi-Xin Chen | Quantum Measured Information | 4 pages, revtex file, no figure | null | null | null | quant-ph | null | A framework for a quantum information theory is introduced that is based on
the measure of quantum information associated with probability distribution
predicted by quantum measuring of state. The entanglement between states of
measured system and "pointer" states of measuring apparatus, which is generated
by dynamical process of quantum measurement, plays a dominant role in
expressing quantum characteristics of information theory. The quantum mutual
information of transmission and reception of quantum states along a noisy
quantum channel is given by the change of quantum measured information. In our
approach, it is not necessary to purify the transmitted state by means of the
reference system. It is also clarified that there exist relations between the
approach given in this letter and those given by other authors.
| [
{
"version": "v1",
"created": "Sat, 12 Jun 1999 02:28:21 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Chen",
"Yi-Xin",
""
]
] |
quant-ph/9906038 | Adonai S. Sant'Anna | Adonai S. Sant'Anna and Alexandre M. S. Santos | Quasi-set-theoretical foundations of statistical mechanics: a research
program | LaTeX, 19 pages, 3 figures | Found.Phys. 30 (2000) 101-120 | null | null | quant-ph | null | Quasi-set theory provides us a mathematical background for dealing with
collections of indistinguishable elementary particles. In this paper, we show
how to obtain the usual statistics (Maxwell-Boltzmann, Bose-Einstein, and
Fermi-Dirac) into the scope of quasi-set theory. We also show that, in order to
derive Maxwell-Boltzmann statistics, it is not necessary to assume that the
particles are distinguishable. In other words, Maxwell-Boltzmann statistics is
possible even in an ensamble of indistinguishable particles, at least from the
theoretical point of view. The main goal of this paper is to provide the
mathematical grounds of a quasi-set-theoretical framework for statistical
mechanics.
| [
{
"version": "v1",
"created": "Sat, 12 Jun 1999 12:47:01 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Sant'Anna",
"Adonai S.",
""
],
[
"Santos",
"Alexandre M. S.",
""
]
] |
quant-ph/9906039 | Tal Mor | Tal Mor and Pawel Horodecki | Teleportation via generalized measurements, and conclusive teleportation | 8 pages, RevTeX, [email protected] | null | null | null | quant-ph | null | In this work we show that teleportation is a special case of a generalized
Einstein, Podolsky, Rosen (EPR) non-locality. Based on the connection between
teleportation and generalized measurements we define conclusive teleportation.
We show that perfect conclusive teleportation can be obtained with any pure
entangled state, and it can be arbitrarily approached with a particular mixed
state.
| [
{
"version": "v1",
"created": "Mon, 14 Jun 1999 23:03:18 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Mor",
"Tal",
""
],
[
"Horodecki",
"Pawel",
""
]
] |
quant-ph/9906040 | Kaare Borchsenius | Kaare Borchsenius | Degenerate space-time paths and the non-locality of quantum mechanics in
a Clifford substructure of space-time | 13 pages, LaTex2e, e-mail: [email protected] | Math.Phys.Electron.J.6:4,1999 | null | null | quant-ph | null | The quantized canonical space-time coordinates of a relativistic point
particle are expressed in terms of the elements of a complex Clifford algebra
which combines the complex properties of SL(2.C) and quantum mechanics. When
the quantum measurement principle is adapted to the generating space of the
Clifford algebra we find that the transition probabilities for twofold
degenerate paths in space-time equals the transition amplitudes for the
underlying paths in Clifford space. This property is used to show that the
apparent non-locality of quantum mechanics in a double slit experiment and in
an EPR type of measurement is resolved when analyzed in terms of the full paths
in the underlying Clifford space. We comment on the relationship of this model
to the time symmetric formulation of quantum mechanics and to the
Wheeler-Feynman model.
| [
{
"version": "v1",
"created": "Sun, 13 Jun 1999 20:37:32 GMT"
},
{
"version": "v2",
"created": "Sat, 20 Nov 1999 20:57:19 GMT"
},
{
"version": "v3",
"created": "Sun, 18 Jun 2000 09:36:34 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Borchsenius",
"Kaare",
""
]
] |
Subsets and Splits
No saved queries yet
Save your SQL queries to embed, download, and access them later. Queries will appear here once saved.