# Matt's arXiv selection: week ending 4 July 2008

From: Matthew Davis <mdavis_at_physics.uq.edu.au>
Date: Mon, 14 Jul 2008 09:16:35 +1000

The following message was sent to the matts_arxiv list by Matthew Davis <mdavis_at_physics.uq.edu.au>

Dear all,

This week there were 25 new preprints and 11 replacements:

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arXiv:0806.4431
Date: Fri, 27 Jun 2008 06:38:41 GMT (8kb)

Title: Dephasing in two decoupled one-dimensional Bose-Einstein condensates and
the subexponential decay of the interwell coherence
Authors: I.E. Mazets, J. Schmiedmayer
Categories: cond-mat.stat-mech cond-mat.other
\\
We provide a simple physical picture of the loss of coherence between two
coherently split one-dimensional Bose-Einstein condensates. The source of the
dephasing is identified with nonlinear corrections to the elementary excitation
energies in either of the two independent condensates. We retrieve the result
by Burkov, Lukin and Demler [Phys. Rev. Lett. 98, 200404 (2007)] on the
subexponential decay of the cocherence for the large time, however, the scaling
of the characteristic decoherence time differs.
\\ ( http://arxiv.org/abs/0806.4431 , 8kb)
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arXiv:0806.4713
Date: Sat, 28 Jun 2008 18:02:10 GMT (28kb)

Title: Equation of state and effective mass of the unitary Fermi gas in a 1D
periodic potential
Authors: Gentaro Watanabe, Giuliano Orso, Franco Dalfovo, Lev P. Pitaevskii,
Sandro Stringari
Categories: cond-mat.supr-con
\\
We study the behavior of a superfluid Fermi gas at unitarity in a 1D optical
lattice by solving the Bogoliubov-de Gennes equations at zero temperature. We
show that the tendency of the lattice to favor the formation of molecules
results in a significant increase of both the effective mass and the
compressibility at low densities, with a consequent large reduction of the
sound velocity. At higher density, when the interparticle distance becomes of
the order of the lattice period, the effective mass reaches its maximum value
and the system becomes less compressible. Predictions for the frequency of the
collective oscillations in the presence of harmonic trapping are also given.
\\ ( http://arxiv.org/abs/0806.4713 , 28kb)
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arXiv:0806.4784
Date: Sun, 29 Jun 2008 20:30:02 GMT (540kb)

Title: Interacting atoms in optical lattices
Authors: Johan Mentink and Servaas Kokkelmans
Categories: cond-mat.other
\\
We propose an easy to use model to solve for interacting atoms in an optical
lattice. This model allows for the whole range of weakly to strongly
interacting atoms, and it includes the coupling between relative and
center-of-mass motion via anharmonic lattice terms. We apply this model to a
high-precision spin dynamics experiment, and we discuss the corrections due to
atomic interactions and the anharmonic coupling. Under suitable experimental
conditions, energy can be transferred between the relative and center-of-mass
motion, and this allows for creation of Feshbach molecules in excited lattice
bands.
\\ ( http://arxiv.org/abs/0806.4784 , 540kb)
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arXiv:0806.4895
Date: Mon, 30 Jun 2008 14:54:05 GMT (8kb)

Title: Collective Excitations of Harmonically Trapped Ideal Gases
Authors: Bert Van Schaeybroeck, Achilleas Lazarides
Categories: cond-mat.other cond-mat.stat-mech
Comments: 4 pages, submitted to special issue of Eur. Phys. J. B "Novel Quantum
Phases and Mesoscopic Physics in Quantum Gases"
\\
We theoretically study the collective excitations of an ideal gas confined in
an isotropic harmonic trap. We give an exact solution to the Boltzmann-Vlasov
equation; as expected for a single-component system, the associated mode
frequencies are integer multiples of the trapping frequency. We show that the
expressions found by the scaling ansatz method are a special case of our
solution. Our findings, however, are most useful in case the trap contains more
than one phase: we demonstrate how to obtain the oscillation frequencies in
case an interface is present between the ideal gas and a different phase.
\\ ( http://arxiv.org/abs/0806.4895 , 8kb)
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arXiv:0806.4961
Date: Mon, 30 Jun 2008 18:14:25 GMT (121kb)

Title: Spectral signatures of the FFLO order parameter in one-dimensional
optical lattices
Authors: M.R. Bakhtiari, M.J. Leskinen, P. Torma
Categories: cond-mat.other
\\
We address an imbalanced two-component atomic Fermi gas restricted by a
one-dimensional (1D) optical lattice and an external harmonic potential, within
the mean-field Bogoliubov-de Gennes (BdG) formalism. We show that
characteristic features of the Fulde-Ferrel-Larkin-Ovchinnikov (FFLO) state are
visible in the RF-spectra and in the momentum resolved photoemission spectra of
the gas. Especially, Andreev states or mid-gap states can be clearly resolved,
which gives a direct experimentally observable signature of the oscillating
order parameter.
\\ ( http://arxiv.org/abs/0806.4961 , 121kb)
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arXiv:0806.4337 (*cross-listing*)
Date: Thu, 26 Jun 2008 15:17:37 GMT (1776kb)

Title: Low-density, one dimensional quantum gases in the presence of a
localised attractive potential
Authors: J. Goold, D. O Donoghue and Th. Busch
Categories: quant-ph cond-mat.mes-hall
\\
We investigate low-density, quantum-degenerate gases in the presence of a
localised attractive potential in the centre of a one-dimensional harmonic
trap.The attractive potential is modelled using a parameterised delta-function,
allowing us to determine all single particle eigenfunctions analytically. From
these we calculate the ground state many-body properties for a system of
spin-polarised fermions and, using the Bose-Fermi mapping theorem, extend the
results to strongly interacting bosonic systems. We discuss the single particle
densities, the pair correlation functions, the reduced single particle density
matrices and the momentum distributions as a function of particle number and
strength of the attractive point potential. As an important experimental
observable, we place special emphasis on spatial coherence properties of such
samples.
\\ ( http://arxiv.org/abs/0806.4337 , 1776kb)
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arXiv:0806.4893
Date: Mon, 30 Jun 2008 13:51:29 GMT (713kb)

Title: Role of the Mean-field in Bloch Oscillations of a Bose-Einstein
Condensate in an Optical Lattice and Harmonic Trap
Authors: R. Zhang, R. E. Sapiro, R. R. Mhaskar, G. Raithel
Categories: physics.atom-ph cond-mat.other
\\
Using the Crank-Nicholson method, we study the evolution of a Bose-Einstein
condensate in an optical lattice and harmonic trap. The condensate is excited
by displacing it from the center of the harmonic trap. The mean field plays an
important role in the Bloch-like oscillations that occur after sufficiently
large initial displacement. We find that a moderate mean field significantly
suppresses the dispersion of the condensate in momentum space. When the mean
field becomes large, soliton and vortex structures appear in the condensate
wavefunction.
\\ ( http://arxiv.org/abs/0806.4893 , 713kb)
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arXiv:0806.4847
Date: Mon, 30 Jun 2008 10:36:30 GMT (449kb)

Title: Quantum reflection of helium atom beams from a microstructured grating
Authors: Bum Suk Zhao, Stephan A. Schulz, Samuel A. Meek, Gerard Meijer, and
Wieland Sch\"ollkopf
Categories: physics.atom-ph
\\
We observe high-resolution diffraction patterns of a thermal-energy
helium-atom beam reflected from a microstructured surface grating at grazing
incidence. The grating consists of 10-$\mu$m-wide Cr strips patterned on a
quartz substrate and has a periodicity of 20 $\mu$m. Fully-resolved diffraction
peaks up to the $7^{\rm th}$ order are observed at grazing angles up to 20
mrad. With changes in de Broglie wavelength or grazing angle the relative
diffraction intensities show significant variations which shed light on the
nature of the atom-surface interaction potential. The observations are
explained in terms of quantum reflection at the long-range attractive
Casimir-van der Waals potential.
\\ ( http://arxiv.org/abs/0806.4847 , 449kb)
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arXiv:0807.0002
Date: Mon, 30 Jun 2008 20:00:14 GMT (19kb)

Title: Superfluidity near phase separation in Bose-Fermi mixtures
Authors: Tilman Enss, Wilhelm Zwerger
Categories: cond-mat.other cond-mat.supr-con
Comments: 5 pages and 3 figures
\\
We study the transition to fermion pair superfluidity in a mixture of
interacting bosonic and fermionic atoms. The fermion interaction induced by the
bosons and the dynamical screening of the condensate phonons due to fermions
are included using the nonperturbative Hamiltonian flow equations. We determine
the bosonic spectrum near the transition towards phase separation and find that
the superfluid transition temperature may be increased substantially due to
phonon damping.
\\ ( http://arxiv.org/abs/0807.0002 , 19kb)
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arXiv:0807.0018
Date: Mon, 30 Jun 2008 21:08:54 GMT (15kb)

Title: Spin Collective Modes of Two-Species Fermi Liquids: Helium-3 and Atomic
Gases near the Feshbach Resonance
Authors: H. P. Dahal, S. Gaudio, J. D. Feldmann, K. S. Bedell
Categories: cond-mat.other
\\
We present theoretical findings on the spin collective modes of a two-species
Fermi liquid, prepared alternatively in a polarized equilibrium or a polarized
non-equilibrium state. We explore the effects on these modes of a diverging
s-wave scattering length, as occurs near a Feshbach resonance in a Fermionic
atomic gas. We compare these atomic gas modes with those of the conventional
Helium-3 system, and we find that they differ from the conventional systems,
and that the gap and spin stiffness are tunable via the Feshbach resonance.
\\ ( http://arxiv.org/abs/0807.0018 , 15kb)
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arXiv:0807.0031
Date: Mon, 30 Jun 2008 22:13:10 GMT (522kb)

Title: Tunneling electro-conductance of atomic Bose condensates
Authors: V. M. Akulin, Yu. E. Lozzovik, I. E. Mazets, A. G. Rudavets, A.
Sarfati
Categories: cond-mat.mes-hall
\\
We consider interaction of an electron with a Bose condensate of atoms having
electron affinity. Though states of the electron attached to atoms form a
continuous band, tunneling through this band is strongly suppressed by quantum
fluctuations of the condensate density. We adapt standard field theory methods
originally developed for description of a particle propagating trough a
disordered potential and present an exactly soluble analytical model of the
process. In contrast with the standard description, we take into account
inelastic processes associated with quantum transitions in the condensate.
Possibilities of the experimental observation of the phenomenon are discussed.
\\ ( http://arxiv.org/abs/0807.0031 , 522kb)
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arXiv:0807.0078
Date: Tue, 1 Jul 2008 08:11:10 GMT (57kb)

Title: Number of closed-channel molecules in the BEC-BCS crossover
Authors: Felix Werner (LKB - Lhomond), Leticia Tarruell (LKB - Lhomond), Yvan
Castin (LKB - Lhomond)
Categories: cond-mat.other
\\
Using a two-channel model, we show that the number of closed channel
molecules in a two-component Fermi gas close to a Feshbach resonance is
directly related to the derivative of the energy of the gas with respect to the
inverse scattering length. We extract this quantity from the fixed node
Monte-Carlo equation of state and we compare to the number of closed channel
molecules measured in the Rice experiment with lithium [Partridge et al., Phys.
Rev. Lett. 95, 020404 (2005)].
\\ ( http://arxiv.org/abs/0807.0078 , 57kb)
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arXiv:0807.0067
Date: Tue, 1 Jul 2008 06:21:51 GMT (63kb)

Title: Analytic treatment of CRIB Quantum Memories for Light using Two-level
Atoms
Authors: J. J. Longdell and G. H\'etet and M. J. Sellars and P. K. Lam
Categories: quant-ph
\\
It has recently been discovered that the optical analogue of a gradient echo
in an optically thick material could form the basis of a optical memory that is
both completely efficient and noise free. Here we present analytical
calculation showing this is the case. There is close analogy between the
operation of the memory and an optical system with two beam splitters. We can
use this analogy to calculate efficiencies as a function of optical depth for a
number of quantum memory schemes based on controlled inhomogeneous broadening.
In particular we show that multiple switching leads to a net 100% retrieval
efficiency for the optical gradient echo even in the optically thin case.
\\ ( http://arxiv.org/abs/0807.0067 , 63kb)
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arXiv:0807.0109
Date: Tue, 1 Jul 2008 10:42:01 GMT (57kb,D)

Title: Single particle nonlocality with completely independent reference states
Authors: J. J. Cooper and J. A. Dunningham
Categories: quant-ph
\\
We describe a scheme to demonstrate the nonlocal properties of a single
particle by showing a violation of Bell's inequality. The scheme is
experimentally achievable as the only inputs are number states and mixed
states, which serve as references to keep track of the experiment'. These
reference states are created completely independently of one another and
correlated only after all the measurement results have been recorded. This
means that any observed nonlocality must solely be due to the single particle
state. All the techniques used are equally applicable to massive particles as
to photons and as such this scheme could be used to show the nonlocality of
atoms.
\\ ( http://arxiv.org/abs/0807.0109 , 57kb)
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arXiv:0807.0114
Date: Tue, 1 Jul 2008 10:54:12 GMT (186kb)

Title: Noisy quadrature of squeezed light and laser cooling
Authors: G.M. Saxena and A. Agarwal
Categories: quant-ph
Journal-ref: Optics communications,267,124-127,2006
\\
The laser cooling of atoms is a result of the combined effect of doppler
shift, light shift and polarization gradient. These are basically undesirable
phenomena. However, they combine gainfully in realizing laser cooling and
trapping of the atoms. In this paper we discuss the laser cooling of atoms in
the presence of the squeezed light with the decay of atomic dipole moment into
noisy quadrature. We show that the higher decay rate of the atomic dipole
moment into the noisy quadrature, which is also an undesirable effect, may
contribute in realizing larger cooling force vis-a-vis normal laser light.
\\ ( http://arxiv.org/abs/0807.0114 , 186kb)
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arXiv:0807.0233
Date: Tue, 1 Jul 2008 20:07:04 GMT (2210kb)

Title: Hidden vortex lattices in a thermally paired superfluid
Authors: E. K. Dahl, E. Babaev, and A. Sudbo
Categories: cond-mat.stat-mech
Comments: 4 pages, 5 figures. Submitted to Physical Review. Online
supplementary material available, see Ref. 6
\\
We study the evolution of rotational response of a hydrodynamic model of a
two-component superfluid with a non-dissipative drag interaction, as the system
undergoes a transition into a paired phase at finite temperature. The
transition manifests itself in a change of (i) vortex lattice symmetry, and
(ii) nature of vortex state. Instead of a vortex lattice, the system forms a
highly disordered tangle which constantly undergoes merger and reconnecting
processes involving different types of vortices, with a "hidden" breakdown of
translational symmetry.
\\ ( http://arxiv.org/abs/0807.0233 , 2210kb)
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arXiv:0807.0251
Date: Tue, 1 Jul 2008 22:42:09 GMT (1000kb,D)

Title: Symmetry-conserving vortex clusters in small rotating clouds of
ultracold bosons
Authors: Igor Romanovsky, Constantine Yannouleas, Uzi Landman
Categories: cond-mat.mes-hall cond-mat.other
Comments: Revtex 4 with 4 color figures. To appear in Physical Review A (Rapid
Communication). For related papers, see http://www.prism.gatech.edu/~ph274cy/
\\
The properties of a special class of correlated many-body wave functions,
named rotating vortex clusters (RVCs), that preserve the total angular momentum
of a small cloud of trapped rotating bosons are investigated. They have lower
energy and provide a superior description for the formation of vortices
compared to the mean-field Gross-Pitaevskii (GP) states that break the
rotational symmetry. The GP vortex states are shown to be wave packets composed
of such RVC states. Our results suggest that, for a small number of bosons, the
physics is different from that of ideal Bose-Einstein condensates which
characterize larger assemblies
\\ ( http://arxiv.org/abs/0807.0251 , 1000kb)
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arXiv:0807.0412
Date: Wed, 2 Jul 2008 17:57:18 GMT (241kb)

Title: Spin 3/2 fermions with attractive interactions in a one-dimensional
optical lattice: phase diagrams, entanglement entropy, and effect of the trap
Authors: G. Roux, S. Capponi, P. Lecheminant, P. Azaria
Categories: cond-mat.str-el
\\
We study spin 3/2 fermionic cold atoms with attractive interactions loaded
into a one-dimensional optical lattice. Using numerical techniques, we
determine the phase diagram for a generic density. For the chosen parameters,
one-particle excitations are gapped and the phase diagram is separated into two
regions: one where the two-particle excitation gap is zero, and one where it is
finite. In the first region, the two-body pairing fluctuations (BCS) compete
with the density ones. In the other one, a molecular superfluid (MS) phase, in
which bound-states of four particles form, competes with the density
fluctuations. The properties of the transition line between these two regions
is studied through the behavior of the entanglement entropy. The physical
features of the various phases, comprising leading correlations, Friedel
oscillations, and excitation spectra, are presented. To make the connection
with experiments, the effect of a harmonic trap confinement is taken into
account. In particular, we emphasize the conditions under which the appealing
MS phase can be realized, and how the phases could be probed by using the
density profiles and the associated structure factor. Lastly, the consequences
on the flux quantization of the different nature of the pairing in the BCS and
MS phases are studied in a situation where the condensate is in a ring
geometry.
\\ ( http://arxiv.org/abs/0807.0412 , 241kb)
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arXiv:0807.0413
Date: Wed, 2 Jul 2008 18:13:29 GMT (2304kb)

Title: Vortices in Superfluid Films on Curved Surfaces
Authors: Ari M. Turner, Vincenzo Vitelli and David R. Nelson
Categories: cond-mat.soft cond-mat.supr-con
\\
We present a systematic study of how vortices in superfluid films interact
with the spatially varying Gaussian curvature of the underlying substrate. The
Gaussian curvature acts as a source for a geometric potential that attracts
(repels) vortices towards regions of negative (positive) Gaussian curvature
independently of the sign of their topological charge. Various experimental
tests involving rotating superfluid films and vortex pinning are first
discussed for films coating gently curved substrates that can be treated in
perturbation theory from flatness. An estimate of the experimental regimes of
interest is obtained by comparing the strength of the geometrical forces to the
vortex pinning induced by the varying thickness of the film which is in turn
caused by capillary effects and gravity. We then present a non-perturbative
technique based on conformal mappings that leads an exact solution for the
geometric potential as well as the geometric correction to the interaction
between vortices. The conformal mapping approach is illustrated by means of
explicit calculations of the geometric effects encountered in the study of some
strongly curved surfaces and by deriving universal bounds on their strength.
\\ ( http://arxiv.org/abs/0807.0413 , 2304kb)
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arXiv:0807.0417
Date: Wed, 2 Jul 2008 18:26:51 GMT (526kb)

Title: Feshbach resonances in ultracold 85Rb-87Rb and 6Li-87Rb mixtures
Authors: Z. Li, S. Singh, T.V. Tscherbul, K.W. Madison
Categories: cond-mat.other
\\
We present an analysis of experimentally accessible magnetic Feshbach
resonances in ultra-cold hetero-nuclear 85Rb-87Rb and 6Li-87Rb mixtures. Using
recent experimental measurements of the triplet scattering lengths for 6Li-87Rb
and 7Li-87Rb mixtures and Feshbach resonances for one combination of atomic
states, we create model potential curves and fine tune them to reproduce the
measured resonances and to predict the location of several experimentally
relevant resonances in Li-Rb collisions. To model 85Rb-87Rb collisions, we use
accurate Rb_2 potentials obtained previously from the analysis of experiments
on 87Rb-87Rb collisions. We find resonances that occur at very low magnetic
fields, below 10 G, which may be useful for entanglement generation in optical
lattices or atom chip magnetic traps.
\\ ( http://arxiv.org/abs/0807.0417 , 526kb)
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arXiv:0807.0254
Date: Tue, 1 Jul 2008 22:54:02 GMT (874kb,D)

Title: Echo Spectroscopy of Atomic Dynamics in a Gaussian Trap via Phase
Imprints
Authors: Daniel Oblak, Juergen Appel, Patrick Windpassinger, Ulrich Busk Hoff,
Niels Kjaergaard, and Eugene S. Polzik
Categories: quant-ph
\\
We report on the collapse and revival of Ramsey fringe visibility when a
spatially dependent phase is imprinted in the coherences of a trapped ensemble
of two-level atoms. The phase is imprinted via the light shift from a Gaussian
laser beam which couples the dynamics of internal and external degrees of
freedom for the atoms in an echo spectroscopy sequence. The observed revivals
are directly linked to the oscillatory motion of atoms in the trap. An
understanding of the effect is important for quantum state engineering of
trapped atoms.
\\ ( http://arxiv.org/abs/0807.0254 , 874kb)
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arXiv:0807.0506
Date: Thu, 3 Jul 2008 08:22:46 GMT (377kb)

Title: Controlling the Population Imbalance of a Bose-Einstein Condensate by a
Symmetry-Breaking Driving Field
Authors: Luis Morales-Molina, Jiangbin Gong
Categories: cond-mat.other
\\
Nonlinear Floquet states associated with a symmetry-breaking driving field
are exploited to control the dynamics of a Bose-Einstein condensate in a
double-well potential. The population imbalance between the two wells is shown
to be controllable by slowly tuning system parameters along a closed path. The
results extend symmetry-breaking-based quantum control to many-body systems and
states.
\\ ( http://arxiv.org/abs/0807.0506 , 377kb)
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arXiv:0807.0572
Date: Thu, 3 Jul 2008 14:16:30 GMT (309kb)

Title: Probing the thermal atoms of a Bose gas through Raman transition
Authors: Patrick Navez
Categories: cond-mat.other
Comments: 10 pages, 6 figures submitted to epjb
\\
We explore the many body physics of a Bose condensed atom gas at finite
temperature through the Raman transition between two hyperfine levels. Unlike
the Bragg scattering where the phonon-like nature of the collective excitations
has been observed, a different branch of thermal atom excitation is found
theoretically in the Raman scattering. This excitation is predicted in the
generalized random phase approximation (GRPA) and has a gapped and parabolic
dispersion relation. The gap energy results from the exchange interaction and
is released during the Raman transition. The scattering rate determined versus
the transition frequency $\omega$ and the transferred momentum $\vc{q}$ show
the corresponding resonance around this gap. Nevertheless, the Raman scattering
process is attenuated by the superfluid part of the gas. The macroscopic wave
function of the condensate deforms its shape in order to screen locally the
external potential displayed by the Raman light beams. This screening is total
for a condensed atom transition in order to prevent the condensate from
incoherent scattering. The experimental observation of this result would
explain some of the reasons for which a superfluid condensate moves coherently
without any friction with its surrounding.
\\ ( http://arxiv.org/abs/0807.0572 , 309kb)
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arXiv:0807.0493 (*cross-listing*)
Date: Thu, 3 Jul 2008 07:11:36 GMT (1100kb)

Title: Resonant sequential scattering in two-frequency-pumping superradiance
from a Bose-Einstein condensate
Authors: Fan Yang, Xiaoji Zhou, Juntao Li, Yuankai Chen, Lin Xia, and Xuzong
Chen
Categories: quant-ph cond-mat.other
\\
We study sequential scattering in superradiance from a Bose-Einstein
condensate pumped by a two-frequency laser beam. We find that the distribution
of atomic side modes presents highly different patterns for various frequency
difference between the two pump components. A novel distribution is observed,
with a frequency difference of eight times the recoil frequency. These
observations reveal that the frequency overlap between the end-fire modes
related to different side modes plays an essential role in the dynamics of
sequential superradiant scattering. The numerical results from a semiclassical
model qualitatively agree with our observations.
\\ ( http://arxiv.org/abs/0807.0493 , 1100kb)
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arXiv:0807.0446
Date: Wed, 2 Jul 2008 20:17:49 GMT (2235kb)

Title: Strongly-interacting bosons in a disordered optical lattice
Authors: M. White, M. Pasienski, D. McKay, S. Zhou, D. Ceperley, B. DeMarco
Categories: physics.atom-ph
\\
Disorder, prevalent in nature, is intimately involved in such spectacular
effects as the fractional quantum Hall effect and vortex pinning in type-II
superconductors. Understanding the role of disorder is therefore of fundamental
interest to materials research and condensed matter physics. Universal
behavior, such as Anderson localization, in disordered non-interacting systems
is well understood. But, the effects of disorder combined with strong
interactions remains an outstanding challenge to theory. Here, we
experimentally probe a paradigm for disordered, strongly-correlated bosonic
systems-the disordered Bose-Hubbard (DBH) model-using a Bose-Einstein
condensate (BEC) of ultra-cold atoms trapped in a completely characterized
disordered optical lattice. We determine that disorder suppresses condensate
fraction for superfluid (SF) or coexisting SF and Mott insulator (MI) phases by
independently varying the disorder strength and the ratio of tunneling to
interaction energy. In the future, these results can constrain theories of the
DBH model and be extended to study disorder for strongly-correlated fermionic
particles.
\\ ( http://arxiv.org/abs/0807.0446 , 2235kb)
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The replacements:

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arXiv:0801.0383
replaced with revised version Fri, 27 Jun 2008 14:01:28 GMT (412kb)

Title: Vortex-lattice formation and melting in a nonrotating Bose-Einstein
condensate
Authors: Gary Ruben, David M. Paganin, and Michael J. Morgan (School of
Physics, Monash University)
Categories: cond-mat.other nlin.PS
introduction and clarified the description of the numerical model. Added
references
\\ ( http://arxiv.org/abs/0801.0383 , 412kb)
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arXiv:0801.2343
replaced with revised version Fri, 27 Jun 2008 17:47:05 GMT (337kb)

Title: Ultracold bosons in lattices with binary disorder
Authors: K.V.Krutitsky, M.Thorwart, R.Egger, R.Graham
Categories: cond-mat.dis-nn cond-mat.other
Journal-ref: Phys.Rev.A 77, 053609 (2008)
DOI: 10.1103/PhysRevA.77.053609
\\ ( http://arxiv.org/abs/0801.2343 , 337kb)
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arXiv:0806.4258
replaced with revised version Fri, 27 Jun 2008 00:07:33 GMT (1234kb)

Title: Photon echoes generated by reversing magnetic field gradients in a
rubidium vapour
Authors: G. H\'etet, M. Hosseini, B. Sparkes, D. Oblak, P. K. Lam and B. C.
Buchler
Categories: quant-ph
\\ ( http://arxiv.org/abs/0806.4258 , 1234kb)
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arXiv:0806.4378
replaced with revised version Mon, 30 Jun 2008 16:39:26 GMT (11kb)

Title: Vortex pseudomomentum and dissipation in a superfluid vortex lattice
Authors: H. M. Cataldo
Categories: cond-mat.stat-mech cond-mat.other physics.flu-dyn
Comments: 11 pages, no figures. Typo corrected in equation (28)
Journal-ref: J. Phys. A: Math. Theor. 41 (2008) 295501 (9pp)
DOI: 10.1088/1751-8113/41/29/295501
\\ ( http://arxiv.org/abs/0806.4378 , 11kb)
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arXiv:0712.0205
replaced with revised version Tue, 1 Jul 2008 12:46:11 GMT (52kb)

Title: Virial equation of state for unitary fermion thermodynamics with
non-Gaussian correlations
Authors: Ji-sheng Chen, Jia-rong Li, Yan-ping Wang, Xiang-jun Xia
Categories: cond-mat.stat-mech hep-ph nucl-th quant-ph
\\ ( http://arxiv.org/abs/0712.0205 , 52kb)
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arXiv:0802.3945
replaced with revised version Tue, 1 Jul 2008 18:45:11 GMT (232kb)

Title: Population imbalanced fermions in harmonically trapped optical lattices
Authors: M. Iskin and C. J. Williams
Categories: cond-mat.supr-con cond-mat.other
Comments: 4 pages with 4 figures, accepted to appear in PRA
\\ ( http://arxiv.org/abs/0802.3945 , 232kb)
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arXiv:cond-mat/0703612
replaced with revised version Thu, 3 Jul 2008 13:11:39 GMT (25kb)

Title: Manifestation of a gap due to the exchange energy in a spinor condensate
Authors: Patrick Navez
Categories: cond-mat.stat-mech
Journal-ref: Phyisca A 387, 4070 (2008)
\\ ( http://arxiv.org/abs/cond-mat/0703612 , 25kb)
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arXiv:0803.0846
replaced with revised version Thu, 3 Jul 2008 09:30:37 GMT (523kb)

Title: Ground State Properties of a Tonks-Girardeau Gas in a Split Trap
Authors: J. Goold and Th. Busch
Categories: cond-mat.other quant-ph
Comments: 7 pages, 10 figures.New Fig. 8 added and text reference to figure in
Sec IV C. New reference [15] added
Journal-ref: Phys. Rev. A 77, 063601 (2008)
\\ ( http://arxiv.org/abs/0803.0846 , 523kb)
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\\
arXiv:0806.0598
replaced with revised version Thu, 3 Jul 2008 17:57:32 GMT (117kb)

Title: Fermion-mediated interactions in a dilute Bose-Einstein condensate
Authors: D. H. Santamore, Eddy Timmermans
Categories: cond-mat.stat-mech physics.atom-ph
Comments: 16 pages, 6 figures, typo corrected
\\ ( http://arxiv.org/abs/0806.0598 , 117kb)
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\\
arXiv:0806.2427
replaced with revised version Thu, 3 Jul 2008 14:27:21 GMT (487kb)

Title: Magnetic interactions of cold atoms with anisotropic conductors
Authors: T. David (1), Y. Japha (1), V. Dikovsky (1), R. Salem (1), C. Henkel
(2), R. Folman (1) ((1) Ben-Gurion University of the Negev, Be'er Sheva,
Israel. (2) Institut f\"ur Physik und Astronomie, Universit\"at Potsdam,
Germany.)
Categories: cond-mat.other cond-mat.mtrl-sci quant-ph
Comments: Selected as a Highlight paper in the European Physical Journal D
Journal-ref: Euro. Phys. J. D. 48, 321-332 (2008)
DOI: 10.1140/epjd/e2008-00119-x
\\ ( http://arxiv.org/abs/0806.2427 , 487kb)
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\\
arXiv:0807.0233
replaced with revised version Thu, 3 Jul 2008 12:42:29 GMT (2377kb)

Title: Hidden vortex lattices in a thermally paired superfluid
Authors: E. K. Dahl, E. Babaev, and A. Sudbo
Categories: cond-mat.stat-mech
Comments: 4 pages, 5 figs. Submitted to Physical Review. Online suppl. material
available; Ref. 6. V2: Fig. 1 re-sent, URL in Ref. 6 corrected
\\ ( http://arxiv.org/abs/0807.0233 , 2377kb)
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Till next time,
Matt.

--
=========================================================================
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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/
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http://www.physics.uq.edu.au/people/mdavis/matts_arXiv/
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Received on Tue Jul 15 2008 - 17:16:38 EST

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