The following message was sent to the matts_arxiv list by Matthew Davis <mdavis_at_physics.uq.edu.au>
Hi all,
Slightly late again this week. Next week's should be slightly early.
Only 23 new papers this time. I heard a slightly amusing story from one of our
graduate students a few days ago: when he started his PhD earlier this year he
thought that he should be reading *every* paper in the weekly arXiv seletion.
He started to get a bit stressed when he was only getting through three or four
and trying to do some work as well. Thankfully someone put him straight before
he decided to quit!
On with the abstracts:
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Paper: cond-mat/0611446
Date: Thu, 16 Nov 2006 21:59:52 GMT (225kb)
Title: Minority Spin Condensate in Spin-Polarized Superfluid $^3$He-A$_1$ Phase
Authors: A. Yamaguchi, S. Kobayashi, H. Ishimoto and H. Kojima
Comments: 13 pages, 4 figures. Accepted for publication in Nature
Subj-class: Other
\\
The spin-polarized superfluid $^3$He A$_1$ phase, which forms below 3 mK in
external magnetic field, serves as a material in which theoretical notions of
fundamental magnetic processes and macroscopic quantum spin phenomena may be
tested. Conventionally, the superfluid component of the A$_1$ phase is
understood to contain only the majority spin condensate having
energetically-favoured paired spins directed along the external field and no
minority spin condensate having paired spins in the opposite direction. We have
developed a novel mechanical spin density detector to measure the spin
relaxation in the A$_1$ phase as functions of temperature, pressure and
magnetic field. The mechanical spin detector is based in principle on the
unique magnetic fountain effect occurring only in the A$_1$ phase (occurring
between two transition temperatures, T$_{c1}$ and T$_{c2}$). Unexpectedly, the
spin relaxation rate increases rapidly as the temperature is decreased towards
T$_{c2}$. Our measurements, together with Leggett-Takagi and Monien-Tewordt
theories, demonstrate that a minute presence of minority spin pairs is
responsible for the unexpected spin relaxation phenomena in A$_1$ phase.
\\ ( http://arXiv.org/abs/cond-mat/0611446 , 225kb)
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Paper: cond-mat/0611450
Date: Fri, 17 Nov 2006 06:07:59 GMT (15kb)
Title: Bethe Ansatz for 1D interacting anyons
Authors: M.T. Batchelor, X.-W. Guan and J.-S. He
Comments: 22 pages
Subj-class: Statistical Mechanics
\\
This article gives a pedagogic derivation of the Bethe Ansatz solution for 1D
interacting anyons. This includes a demonstration of the subtle role of the
anyonic phases in the Bethe Ansatz arising from the anyonic commutation
relations. The thermodynamic Bethe Ansatz equations defining the temperature
dependent properties of the model are also derived, from which some groundstate
properties are obtained.
\\ ( http://arXiv.org/abs/cond-mat/0611450 , 15kb)
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Paper: cond-mat/0611456
Date: Fri, 17 Nov 2006 10:44:49 GMT (521kb)
Title: Mean field theory and fluctuation spectrum of a pumped, decaying
Bose-Fermi system across the quantum condensation transition
Authors: M. H. Szymanska, J. Keeling, P. B. Littlewood
Comments: 28 pages, 11 figures
Subj-class: Other
\\
We study the mean-field theory, and the properties of fluctuations, in an out
of equilibrium Bose-Fermi system, across the transition to a quantum condensed
phase. The system is driven out of equilibrium by coupling to multiple baths,
which are not in equilibrium with each other, and thus drive a flux of
particles through the system.
We derive the self-consistency condition for an uniform condensed steady
state. This condition can be compared both to the laser rate equation and to
the Gross-Pitaevskii equation of an equilibrium condensate. We study
fluctuations about the steady state, and discuss how the multiple baths
interact to set the system's distribution function. In the condensed system,
there is a soft phase (Bogoliubov, Goldstone) mode, diffusive at small momenta
due to the presence of pump and decay, and we discuss how one may determine the
field-field correlation functions properly including such soft phase modes. In
the infinite system, the correlation functions differ both from the laser and
from an equilibrium condensate; we discuss how in a finite system, the laser
limit may be recovered.
\\ ( http://arXiv.org/abs/cond-mat/0611456 , 521kb)
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Paper: quant-ph/0611181
Date: Thu, 16 Nov 2006 23:00:27 GMT (154kb)
Title: Adiabatic frequency conversion of quantum optical information in atomic
vapor
Authors: Frank Vewinger, Juergen Appel, Eden Figueroa, A. I. Lvovsky
\\
We experimentally demonstrate a quantum communication protocol that enables
frequency conversion and routing of quantum optical information in an adiabatic
and thus robust way. The protocol is based on electromagnetically-induced
transparency in systems with multiple excited levels: transfer and/or
distribution of optical states between different signal modes is implemented by
adiabatically changing the control fields. The proof-of-principle experiment is
performed using the hyperfine levels of the rubidium D1 line.
\\ ( http://arXiv.org/abs/quant-ph/0611181 , 154kb)
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Paper: quant-ph/0611185
Date: Fri, 17 Nov 2006 10:20:15 GMT (116kb)
Title: Test of the isotopic and velocity selectivity of a lithium atom
interferometer by magnetic dephasing
Authors: Marion Jacquey (LCAR), Alain Miffre (LCAR, LASIM), Matthias
B\"{u}chner (LCAR), G\'{e}rard Tr\'{e}nec (LCAR), Jacques Vigu\'{e} (LCAR)
Proxy: ccsd hal-00114617
\\
A magnetic field gradient applied to an atom interferometer induces a
$M$-dependent phase shift which results in a series of decays and revivals of
the fringe visibility. Using our lithium atom interferometer based on Bragg
laser diffraction, we have measured the fringe visibility as a function of the
applied gradient. We have thus tested the isotopic selectivity of the
interferometer, the velocity selective character of Bragg diffraction for
different diffraction orders as well as the effect of optical pumping of the
incoming atoms. All these observations are qualitatively understood but a
quantitative analysis requires a complete model of the interferometer.
\\ ( http://arXiv.org/abs/quant-ph/0611185 , 116kb)
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Paper: physics/0611175
Date: Fri, 17 Nov 2006 20:03:34 GMT (745kb)
Title: Light forces in ultracold photoassociation
Authors: E. Gomez (1), A. T. Black (1), L. D. Turner (1), E. Tiesinga (1), P.
D. Lett (1), ((1)National Institute of Standards and Technology,
Gaithersburg)
Comments: 7 pages, 3 figures
Subj-class: Atomic Physics
\\
We study the time-resolved photoassociation of ultracold sodium in an optical
dipole trap. The photoassociation laser excites pairs of atoms to molecular
states of large total angular momentum at high intensities (above 20
kW/cm$^{2}$). Such transitions are generally suppressed at ultracold
temperatures by the centrifugal barriers for high partial waves. Time-resolved
ionization measurements reveal that the atoms are accelerated by the dipole
potential of the photoassociation beam. We change the collision energy by
varying the potential depth, and observe a strong variation of the
photoassociation rate. These results demonstrate the important role of light
forces in cw photoassociation at high intensities.
\\ ( http://arXiv.org/abs/physics/0611175 , 745kb)
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Paper: cond-mat/0611421
Date: Thu, 16 Nov 2006 02:53:26 GMT (51kb)
Title: Pairing in Asymmetrical Fermi Systems with Intra- and Inter-Species
Correlations
Authors: Renyuan Liao and Khandker F. Quader (Dept of Physics, Kent State
University)
Comments: 5 pages, 3 figures
Subj-class: Superconductivity; Strongly Correlated Electrons; Atomic Physics
\\
We consider inter- and intra-species pairing interactions in an asymmetrical
Fermi system. Using equation of motion method, we obtain coupled mean-field
equations for superfluid gap functions and population densities. We construct a
phase diagram across BCS-BEC regimes. Due to intra-species correlations, the
BCS singlet superfluid state can sustain finite polarizations, $P$. For larger
$P$, we find phase separations in BCS and BEC regimes. A superfluid phase
exists for all $P$ deep in BEC regime. Our results may apply to pairing in
ultracold fermions, nuclear and quark matter physics.
\\ ( http://arXiv.org/abs/cond-mat/0611421 , 51kb)
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Paper: cond-mat/0611479
Date: Fri, 17 Nov 2006 21:38:06 GMT (40kb)
Title: Competition between local potentials and attractive particle-particle
interactions in superlattices
Authors: N. A. Lima, A. L. Malvezzi and K. Capelle
Comments: 8 pages, 2 figures
Subj-class: Strongly Correlated Electrons; Materials Science
\\
Naturally occuring or man-made systems displaying periodic spatial
modulations of their properties on a nanoscale constitute superlattices. Such
modulated structures are important both as prototypes of simple
nanotechnological devices and as particular examples of emerging spatial
inhomogeneity in interacting many-electron systems. Here we investigate the
effect different types of modulation of the system parameters have on the
ground-state energy and the charge-density distribution of the system. The
superlattices are described by the inhomogeneous attractive Hubbard model, and
the calculations are performed by density-functional and density-matrix
renormalization group techniques. We find that modulations in local electric
potentials are much more effective in shaping the system's properties than
modulations in the attractive on-site interaction. This is the same conclusions
we previously (Phys. Rev. B 71, 125130) obtained for repulsive interactions,
suggesting that it is not an artifact of a specific state, but a general
property of modulated structures.
\\ ( http://arXiv.org/abs/cond-mat/0611479 , 40kb)
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Paper: cond-mat/0611487
Date: Sat, 18 Nov 2006 12:11:08 GMT (454kb)
Title: Time modulation of atom sources
Authors: A. del Campo, J. G. Muga, M. Moshinsky
Comments: 13 pages, 8 figures
Subj-class: Other
\\
Sudden turn-on of a matter-wave source leads to characteristic oscillations
of the probability density which are the hallmark feature of diffraction in
time. The apodization of matter waves relies on the use of smooth aperture
functions which suppress such oscillations. The analytical dynamics arising
with different aperture functions are discussed systematically for switching-on
processes, and for single and many-pulse formation procedures. The possibility
and time scale of a revival of the diffraction-in-time pattern is also
analysed. Similar modulations in time of the pulsed output coupling in
atom-lasers are responsible for the dynamical evolution and characteristics of
the beam profile. For multiple pulses, different phase schemes and regimes are
described and compared. Strongly overlapping pulses lead to a saturated,
constant beam profile in time and space, up to the revival phenomenon.
\\ ( http://arXiv.org/abs/cond-mat/0611487 , 454kb)
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Paper: cond-mat/0611490
Date: Sat, 18 Nov 2006 14:07:52 GMT (11kb)
Title: Static Properties of Trapped Bose Gases at Finite Temperature: I.
Thomas- Fermi Limit
Authors: Benarous Mohamed and Houria Chachou Samet
Comments: 11 pages
Subj-class: Statistical Mechanics
\\
We rely on a time-dependent variational approach to derive the dynamics of a
trapped self-interacting Bose gas at finite temperature. We then analyze the
static situation both at zero and finite temperature in the Thomas-Fermi limit.
We derive analytic expressions for the condensate radius and the chemical
potential at finite temperature and obtain encouraging results for the various
density profiles. A novel image of the way the condensed and non condensed
phases mix up emerges from our calculations.
\\ ( http://arXiv.org/abs/cond-mat/0611490 , 11kb)
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Paper: cond-mat/0611506
Date: Sun, 19 Nov 2006 21:00:22 GMT (13kb)
Title: Schrodinger equation for the one particle density matrix of thermal
systems: An alternative formulation of Bose-Einstein condensation
Authors: Subodha Mishra and Peter Pfeifer
Comments: 4 pages, 2 figures
Subj-class: Statistical Mechanics
\\
We formulate a linear Schrodinger equation with the temperature-dependent
potential for the one-particle density matrix and obtain the condensation
temperature of the Bose-Einstein condensate from a bound-state condition for
the Schrodinger equation both with and without the confining trap. The results
are in very good agreement with those of the full statistical physics
treatment. This is an alternative to the Bose-Einstein condensation in the
standard ideal Bose gas treatment.
\\ ( http://arXiv.org/abs/cond-mat/0611506 , 13kb)
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Paper: cond-mat/0611510
Date: Mon, 20 Nov 2006 06:34:36 GMT (669kb)
Title: Ground-state properties of the attractive one-dimensional Bose-Hubbard
model
Authors: Norman Oelkers and Jon Links
Comments: 17 pages, 12 figures
Subj-class: Statistical Mechanics
\\
We study the ground state of the attractive one-dimensional Bose-Hubbard
model, and in particular the nature of the crossover between the weak
interaction and strong interaction regimes for finite system sizes. Indicator
properties like the gap between the ground and first excited energy levels, and
the incremental ground-state wavefunction overlaps are used to locate
transitions. Using mean-field theory, we show there are two distinct
transitions connected to spontaneous symmetry breaking of the ground state. The
first transition arises in an analysis valid for large L with finite N, where L
is the number of lattice sites and N is the total particle number. An
alternative approach valid for large N with finite L yields a second
transition. For small system sizes we numerically investigate the model, and
observe that there are signatures of both transitions. We compare with exact
results from Bethe ansatz methods in several limiting cases to explore the
validity for these numerical and mean-field schemes. The results indicate that
for finite attractive systems there are generically three ground-state phases
of the model.
\\ ( http://arXiv.org/abs/cond-mat/0611510 , 669kb)
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Paper: cond-mat/0611512
Date: Mon, 20 Nov 2006 07:21:32 GMT (634kb)
Title: A class of permanent magnetic lattices for ultracold atoms
Authors: Saeed Ghanbari, Tien D Kieu and Peter Hannaford
Comments: 18 pages
Subj-class: Other
\\
We report on a class of configurations of permanent magnets on an atom chip
for producing 1D and 2D periodic arrays of magnetic microtraps with non-zero
potential minima and variable barrier height for trapping and manipulating
ultracold atoms and quantum degenerate gases. We present analytical expressions
for the relevant physical quantities and compare them with our numerical
results and with some previous numerical calculations. In one of the
configurations of permanent magnets, we show how it is possible by changing the
angle between the crossed periodic arrays of magnets to go from a 1D array of
2D microtraps to a 2D array of 3D microtraps and thus to continuously vary the
barrier heights between the microtraps. This suggests the possibility of
performing a type of `mechanical' BEC to Mott insulator quantum phase
transition in a magnetic lattice. We also discuss a configuration of magnets
which could realize a two-qubit quantum gate in a magnetic lattice.
\\ ( http://arXiv.org/abs/cond-mat/0611512 , 635kb)
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Paper: cond-mat/0611522
Date: Mon, 20 Nov 2006 14:08:00 GMT (214kb)
Title: Variational study of hard-core bosons in a 2-D optical lattice using
Projected Entangled Pair States (PEPS)
Authors: V. Murg, F. Verstraete, J. I. Cirac
Comments: 9 pages, 9 figures
Subj-class: Other
\\
We have studied the system of hard-core bosons on a 2-D optical lattice using
a variational algorithm based on projected entangled-pair states (PEPS). We
have investigated the ground state properties of the system as well as the
responses of the system to sudden changes in the parameters. We have compared
our results to mean field results based on a Gutzwiller ansatz.
\\ ( http://arXiv.org/abs/cond-mat/0611522 , 214kb)
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Paper (*cross-listing*): gr-qc/0611096
Date: Fri, 17 Nov 2006 16:34:37 GMT (9kb)
Title: Analog Models beyond Kinematics
Authors: Serena Fagnocchi
Comments: 8 pages; Talk given at ISSP (Erice, September 2006); to appear on
World Scientific
Subj-class: General Relativity and Quantum Cosmology; Other
\\
In this paper I discuss the extension of the analogy between gravitation and
some systems of condensed matter physics from kinematics to dynamics. I will
focus my attention on two applications of the analogy to the dynamics of fluids
that have been recently proposed: the study of backreaction effects and the
calculation of the depletion in Bose-Einstein condensates, showing how this
extension is possible and stressing the main differences with respect to the
gravitational context. I will conclude with some remarks about the actual
reliability of the proposed scheme, pointing out the basis issues that have
still to be addressed.
\\ ( http://arXiv.org/abs/gr-qc/0611096 , 9kb)
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Paper (*cross-listing*): nucl-th/0611064
Date: Fri, 17 Nov 2006 07:11:09 GMT (60kb)
Title: Indication of BCS-BEC crossover behavior in halo nuclei
Authors: K. Hagino, H. Sagawa, J. Carbonell, and P. Schuck
Comments: 4 pages, 3 eps figures
Subj-class: Nuclear Theory; Superconductivity
\\
We investigate the spatial structure of two-neutron wave function in a
Borromean nucleus $^{11}$Li using a three-body model in which two valence
neutrons interact with each other by a density-dependent contact force. The
behavior of the neutron Cooper pair at different densities is simulated by
calculating the two-neutron wave function at several distances between the core
nucleus and the center of mass of the two neutrons. We find that the neutron
pair wave function in $^{11}$Li has an oscillation at normal density, while it
becomes a well localized single peak in the dilute density region around the
nuclear surface.
These features are in close analogue to the BCS-BEC crossover of the Cooper
pair wave function found in the infinite nuclear matter. The present results
also provide a unified picture of the di-neutron and the cigar-like
configurations in Borromian nuclei as a manifestation of the BCS-BEC crossover
phenomenon.
\\ ( http://arXiv.org/abs/nucl-th/0611064 , 60kb)
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Paper: quant-ph/0611190
Date: Sat, 18 Nov 2006 01:03:21 GMT (13kb)
Title: Precision measurement with an optical Josephson junction
Authors: H. T. Ng, K. Burnett and J. A. Dunningham
Comments: 6 pages, 1 figure
\\
We study a new type of Josephson device, the so-called ``optical Josephson
junction'' as proposed in Phys. Rev. Lett. {\bf 95}, 170402 (2005). Two
condensates are optically coupled through a waveguide by a pair of Bragg beams.
This optical Josephson junction is analogous to the usual Josephson junction of
two condensates weakly coupled via tunneling. We discuss the use of this
optical Josephson junction, for making precision measurements.
\\ ( http://arXiv.org/abs/quant-ph/0611190 , 13kb)
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Paper: quant-ph/0611204
Date: Mon, 20 Nov 2006 02:57:13 GMT (390kb)
Title: Squeezed light for bandwidth limited atom optics experiments at the
Rubidium D1 line
Authors: G. H\'etet, O. Gl\"ockl, K. A. Pilypas, C.C. Harb, B.C. Buchler, H.-A.
Bachor, P.K. Lam
Comments: 8 pages, 3 figures. Accepted for Journal of Physics B
\\
We report on the generation of more than 5 dB of vacuum squeezed light at the
Rubidium D1 line (795 nm) using periodically poled KTiOPO$_{4}$ (PPKTP) in an
optical parametric oscillator. We demonstrate squeezing at low sideband
frequencies, making this source of non-classical light compatible with
bandwidth limited atom optics experiments. When PPKTP is operated as a
parametric amplifier, we show a noise reduction of 4 dB stably locked within
the 150 kHz-500 kHz frequency range. This matches the bandwidth of
Electromagnetically Induced Transparency (EIT) in Rubidium hot vapour cells
under the condition of large information delay.
\\ ( http://arXiv.org/abs/quant-ph/0611204 , 390kb)
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Paper: cond-mat/0611561
Date: Tue, 21 Nov 2006 16:24:50 GMT (887kb)
Title: Free fermion antibunching in a degenerate atomic Fermi gas released from
an optical lattice
Authors: T. Rom, Th. Best, D. van Oosten, U. Schneider, S. Foelling, B. Paredes
and I. Bloch
Comments: (Nature, in press)
Subj-class: Other
\\
Noise in a quantum system is fundamentally governed by the statistics and the
many-body state of the underlying particles. Whereas for bosonic particles the
correlated noise observed for e.g. photons or bosonic neutral atoms can still
be explained within a classical field description with fluctuating phases, the
anticorrelations in the detection of fermionic particles have no classical
analogue. The observation of such fermionic antibunching is so far scarce and
has been confined to electrons and neutrons. Here we report on the first direct
observation of antibunching of neutral fermionic atoms. Through an analysis of
the atomic shot noise in a set of standard absorption images, of a gas of
fermionic 40K atoms released from an optical lattice, we find reduced
correlations for distances related to the original spacing of the trapped
atoms. The detection of such quantum statistical correlations has allowed us to
characterise the ordering and temperature of the Fermi gas in the lattice.
Moreover, our findings are an important step towards revealing fundamental
fermionic many-body quantum phases in periodic potentials, which are at the
focus of current research.
\\ ( http://arXiv.org/abs/cond-mat/0611561 , 887kb)
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Paper: cond-mat/0611566
Date: Tue, 21 Nov 2006 19:13:48 GMT (47kb)
Title: Measurement of the Entropy and Critical Temperature of a Strongly
Interacting Fermi Gas
Authors: L. Luo, B. Clancy, J. Joseph, J. Kinast, and J. E. Thomas
Comments: 16 pages, 3 figures
Subj-class: Other
\\
We report a model-independent measurement of the entropy, energy, and
critical temperature of a degenerate, strongly interacting Fermi gas of atoms.
The total energy is determined from the mean square cloud size in the strongly
interacting regime, where the gas exhibits universal behavior. The entropy is
measured by sweeping a bias magnetic field to adiabatically tune the gas from
the strongly interacting regime to a weakly interacting regime, where the
entropy is known from the cloud size after the sweep. The dependence of the
entropy on the total energy quantitatively tests predictions of the
finite-temperature thermodynamics.
\\ ( http://arXiv.org/abs/cond-mat/0611566 , 47kb)
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Paper (*cross-listing*): math-ph/0611043
Date: Fri, 17 Nov 2006 20:40:28 GMT (18kb)
Title: Interacting Bose and Fermi gases in low dimensions and the Riemann
hypothesis
Authors: Andr\'e LeClair
Subj-class: Mathematical Physics; Statistical Mechanics; Number Theory
\\
We apply the S-matrix based finite temperature formalism we recently
developed to non-relativistic Bose and Fermi gases in 1+1 and 2+1 dimensions.
In the 2+1 dimensional case, the free energy is given in terms of Roger's
dilogarithm in a way analagous to the relativistic 1+1 dimensional case. The 1d
fermionic case with a quasi-periodic 2-body potential provides a physical
framework for understanding the Riemann hypothesis.
\\ ( http://arXiv.org/abs/math-ph/0611043 , 18kb)
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Paper: quant-ph/0611219
Date: Tue, 21 Nov 2006 18:28:01 GMT (27kb)
Title: On experimental procedures for entanglement verification
Authors: S.J. van Enk, N. Lutkenhaus, and H.J. Kimble
Comments: 14 pages
\\
We give an overview of different types of entanglement that can be generated
in experiments, as well as of various protocols that can be used to verify or
quantify entanglement. We propose several criteria that, we argue, ought to be
applied to experimental entanglement verification procedures. Explicit examples
demonstrate that not following these criteria will tend to result in
overestimating the amount of entanglement generated in an experiment or in
infering entanglement when there is none. We distinguish protocols meant to
refute or eliminate hidden-variable models from those meant to verify
entanglement.
\\ ( http://arXiv.org/abs/quant-ph/0611219 , 27kb)
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Paper: cond-mat/0611578
Date: Wed, 22 Nov 2006 09:32:03 GMT (66kb)
Title: Trapped Resonant Fermions above Superfluid Transition Temperature
Authors: Chi-Ho Cheng and Sung-Kit Yip
Comments: 9 pages, 4 figures
Subj-class: Superconductivity; Other
\\
We investigate trapped resonant fermions with unequal populations within the
local density approximation above the superfluid transition temperature. By
tuning the attractive interaction between fermions via Feshbach resonance, the
system evolves from weakly interacting fermi gas to strongly interacting fermi
gas, and finally becomes bose-fermi mixture. The density profiles of fermions
are examined and compared with experiments. We also point out the simple
relationships between the local density, the axial density, and the gas
pressure within the local density approximation.
\\ ( http://arXiv.org/abs/cond-mat/0611578 , 66kb)
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Paper: cond-mat/0611584
Date: Wed, 22 Nov 2006 13:14:07 GMT (67kb)
Title: Momentum distribution dynamics of a Tonks-Girardeau gas: Bragg
reflections of a quantum many-body wavepacket
Authors: R. Pezer and H. Buljan
Subj-class: Other
\\
The dynamics of the momentum distribution and the reduced single-particle
density matrix (RSPDM) of a Tonks-Girardeau (TG) gas is studied in the context
of Bragg-reflections of a many-body wavepacket. We find strong suppression of a
Bragg-reflection peak for a dense TG wavepacket; our observation illustrates
dependence of the momentum distribution on the interactions/wavefunction
symmetry. The momentum distribution is calculated with a fast algorithm based
on a formula expressing the RSPDM via a dynamically evolving single-particle
basis.
\\ ( http://arXiv.org/abs/cond-mat/0611584 , 67kb)
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Paper: quant-ph/0611221
Date: Tue, 21 Nov 2006 22:26:45 GMT (714kb)
Title: Self ordering and superradiant backscattering of a gaseous beam in a
ring cavity with counter propagating pump
Authors: C. Maes, J. Asboth, H. Ritsch
Comments: 18 pages 11 figures
\\
We study the threshold conditions of spatial self organization combined with
collective coherent optical backscattering of a thermal gaseous beam moving in
a high Q ring cavity with counter propagating pump. We restrict ourselves to
the limit of large detuning between the particles optical resonances and the
light field, where spontaneous emission is negligible and the particles can be
treated as polarizable point masses. Using a linear stability analysis in the
accelerated rest frame of the particles we derive an analytic bounds for the
selforganization as a function of particle number,average velocity, temperature
and resonator parameters. We check our results by a numerical iteration
procedure as well as by direct simulations of the N-particle dynamics. Due to
momentum conservation the backscattered intensity determines the average force
on the cloud, which gives the conditions for stopping and cooling a fast
molecular beam.
\\ ( http://arXiv.org/abs/quant-ph/0611221 , 714kb)
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Paper: quant-ph/0611228
Date: Wed, 22 Nov 2006 12:14:44 GMT (292kb)
Title: Spectral theory of quantum memory and entanglement via Raman scattering
of light by an atomic ensemble
Authors: O.S. Mishina, D.V. Kupriyanov, J.H. Muller, E.S. Polzik
Comments: 14 pages, 6 figures. submitted to PRA
\\
We discuss theoretically quantum interface between light and a spin polarized
ensemble of atoms with the spin $\geq 1$ based on an off-resonant Raman
scattering. We present the spectral theory of the light-atoms interaction and
show how particular spectral modes of quantum light couple to spatial modes of
the extended atomic ensemble. We show how this interaction can be used for
quantum memory storage and retrieval and for deterministic entanglement
protocols. The proposed protocols are attractive due to their simplicity since
they involve just a single pass of light through atoms without the need for
elaborate pulse shaping or quantum feedback. As a practically relevant example
we consider the interaction of a light pulse with hyperfine components of D-1
line of 87Rb. The quality of the proposed protocols is verified via analytical
and numerical analysis.
\\ ( http://arXiv.org/abs/quant-ph/0611228 , 292kb)
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The replacements: apologies to Dr A.P. Itin, when I missed one of his replaced
manuscripts last week.
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Missed last week:
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Paper: cond-mat/0610767
replaced with revised version Tue, 14 Nov 2006 06:56:47 GMT
Title: Universality in nonadiabatic behaviour of classical actions in
nonlinear models with separatrix crossings
Authors: A.P. Itin, S. Watanabe
Comments: 17 pages, 11 figures Comment to ver. 2: some typos and notations
in figures are corrected
Subj-class: Other
\\ ( http://arxiv.org/abs/cond-mat/0610767 )
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Paper: cond-mat/0602224
replaced with revised version Fri, 17 Nov 2006 00:56:12 GMT (107kb)
Title: Critical Temperature and Thermodynamics of Attractive Fermions at
Unitarity
Authors: Evgeni Burovski, Nikolay Prokof'ev, Boris Svistunov, and Matthias
Troyer
Comments: 4+1 pages, 4 figures, published version + erratum
Subj-class: Statistical Mechanics; Superconductivity
Journal-ref: Phys. Rev. Lett. 96, 160402 (2006)
DOI: 10.1103/PhysRevLett.96.160402
\\ ( http://arXiv.org/abs/cond-mat/0602224 , 107kb)
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Paper: cond-mat/0406454
replaced with revised version Mon, 20 Nov 2006 03:22:53 GMT (606kb)
Title: Vortex Dynamics Near the Surface of a Bose-Einstein Condensate
Authors: U. Al Khawaja
Comments: 8 pages, 9 figures
Subj-class: Statistical Mechanics
Journal-ref: Phys. Rev. A 71, 063611 (2005)
\\ ( http://arXiv.org/abs/cond-mat/0406454 , 606kb)
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Paper: cond-mat/0603479
replaced with revised version Mon, 20 Nov 2006 13:42:17 GMT (8kb)
Title: Ground state energy density of a dilute Bose gas in the canonical
transformation
Authors: Hyun Sik Noh, Sang-Hoon Kim, Chul Koo Kim, and Mukunda P. Das
Comments: 5 pages, 0 figure
Subj-class: Statistical Mechanics
\\ ( http://arXiv.org/abs/cond-mat/0603479 , 8kb)
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Paper: cond-mat/0607618
replaced with revised version Mon, 20 Nov 2006 16:48:08 GMT (65kb)
Title: Single-particle versus pair condensation of hard-core bosons with
correlated hopping
Authors: K.P. Schmidt, J. Dorier, A. Laeuchli, and F. Mila
Comments: 8 pages, 7 figures
Subj-class: Other
Journal-ref: Phys. Rev. B 74, 174508 (2006)
DOI: 10.1103/PhysRevB.74.174508
\\ ( http://arXiv.org/abs/cond-mat/0607618 , 65kb)
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Paper: cond-mat/0608690
replaced with revised version Sun, 19 Nov 2006 02:14:25 GMT (95kb)
Title: Hidden symmetry and quantum phases in spin-3/2 cold atomic systems
Authors: Congjun Wu
Subj-class: Strongly Correlated Electrons
\\ ( http://arXiv.org/abs/cond-mat/0608690 , 95kb)
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Paper: cond-mat/0610367
replaced with revised version Wed, 22 Nov 2006 13:19:42 GMT (9kb)
Title: The depletion in Bose Einstein condensates using Quantum Field Theory in
curved space
Authors: Roberto Balbinot, Serena Fagnocchi, Alessandro Fabbri
Comments: 4 pages, no figure. Typos corrected
Subj-class: Other; Soft Condensed Matter
\\ ( http://arXiv.org/abs/cond-mat/0610367 , 9kb)
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Paper: quant-ph/0610114
replaced with revised version Tue, 21 Nov 2006 21:55:21 GMT (139kb)
Title: Rotation of atoms in a two dimensional lattice with a harmonic trap
Authors: T. Wang, S. Yelin
Comments: 4 pages, some paragraphs were refrased, typos corrected
\\ ( http://arXiv.org/abs/quant-ph/0610114 , 139kb)
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Till next week,
Matt.
-- ========================================================================= Dr M. J. Davis, Senior Lecturer in Physics School of Physical Sciences, email: mdavis_at_physics.uq.edu.au University of Queensland, ph : +61 7 334 69824 Brisbane, QLD 4072, fax : +61 7 336 51242 Australia. http://www.physics.uq.edu.au/people/mdavis/ ========================================================================= Matt's arXiv selection: weekly summary of cold-atom papers from arXiv.org http://www.physics.uq.edu.au/people/mdavis/matts_arXiv/ ========================================================================= Legal stuff: Unless stated otherwise, this e-mail represents only the views of the sender and not the views of the University of Queensland =========================================================================Received on Thu Nov 30 2006 - 09:49:53 EST
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