[Matts-arxiv] Matt's arXiv selection: week ending 17 July 2009

From: Matthew Davis <mdavis_at_physics.uq.edu.au>
Date: Sat, 05 Sep 2009 20:03:40 +1000

Dear subscribers,

This week's listing was compiled by Simon Haine. There are 23 new preprints and
  7 replacements:

\\
arXiv:0907.1866
Date: Fri, 10 Jul 2009 16:32:05 GMT (309kb,D)

Title: Density profiles of an interacting three-component normal Fermi gas in a
harmonic trap
Authors: Theja N. De Silva
Categories: cond-mat.quant-gas
Comments: Total six pages with five figures
\\
We use Thomas-Fermi approximation to investigate the density variations of an
interacting three-component normal Fermi gas in a harmonic trap. We consider
both attractive and repulsive interactions between different pairs of fermions
and study the effect of population imbalance on densities. We find that the
density profiles significantly deviate from those of non-interacting profiles
and extremely sensitive to the interactions and population imbalance. Unlike
two-component Fermi systems, we find density imbalance in the trap even for
balanced populations. For some range of parameters, one component completely
repels from the trap center giving rise a donut shape density profile.
\\ ( http://arxiv.org/abs/0907.1866 , 309kb)
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arXiv:0907.1873
Date: Fri, 10 Jul 2009 17:24:24 GMT (165kb)

Title: Superposition of flux-qubit states and the law of angular momentum
conservation
Authors: A.V. Nikulov
Categories: cond-mat.supr-con cond-mat.mes-hall
Comments: 6 pages, 1 figure
\\
It is shown that the assumptions on macroscopic quantum tunneling and on
superposition of two macroscopically distinct quantum states of superconducting
loop, considered as flux qubit by many authors, contradict to the fundamental
law of angular momentum conservation and the universally recognized quantum
formalism.
\\ ( http://arxiv.org/abs/0907.1873 , 165kb)
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arXiv:0907.1757
Date: Fri, 10 Jul 2009 08:39:11 GMT (8kb)

Title: Phase-space deformation of a dipolar Fermi gas in free expansion
Authors: Takushi Nishimura and Tomoyuki Maruyama
Categories: cond-mat.quant-gas
\\
We theoretically investigate a polarized dipolar Fermi gas in free expansion.
The dipolar-dipolar inter-particle interaction deforms phase-space distribution
in trap and also in the expansion. We exactly predict the minimal quadrupole
deformation in the expansion for the high-temperature Maxwell-Boltzmann (MB)
and zero-temperature Thomas-Fermi (TF) gases in the Hartree-Fock and
Landau-Vlasov approaches by developing a new deformation ansatz. In conclusion,
we reveal a scaling law associated with the Liouville's theorem in the
long-time behaviors of the MB and TF gases and also provide a proper
theoretical approach to develop the time-of-flight method for the dipolar Fermi
gas.
\\ ( http://arxiv.org/abs/0907.1757 , 8kb)
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\\
arXiv:0907.1881
Date: Fri, 10 Jul 2009 18:27:51 GMT (1178kb)

Title: Mesoscopic cavity-QED: the physics behind off-resonant cavity excitation
by a single quantum dot
Authors: Martin Winger, Thomas Volz, Guillaume Tarel, Stefano Portolan, Antonio
Badolato, Kevin Hennessy, Evelyn Hu, Alexios Beveratos, Jonathan Finley,
Vincenzo Savona, Atac Imamoglu
Categories: cond-mat.mes-hall
Comments: 7 pages, 4 figures
\\
Cavity quantum-electrodynamics experiments using an atom coupled to a single
radiation-field mode have played a central role in testing foundations of
quantum mechanics, thus motivating solid-state implementations using single
quantum dots coupled to monolithic nano-cavities. In stark contrast to their
atom based counterparts, the latter experiments revealed strong cavity
emission, even when the quantum dot is far off resonance. Here we present
experimental and theoretical results demonstrating that this effect arises from
the mesoscopic nature of quantum dot confinement, ensuring the presence of a
quasi-continuum of transitions between excited quantum dot states that are
enhanced by the cavity mode. Our model fully explains photon correlation
measurements demonstrating that photons emitted at the cavity frequency are
essentially uncorrelated with each other even though they are generated by a
single quantum dot.
\\ ( http://arxiv.org/abs/0907.1881 , 1178kb)
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arXiv:0907.1657
Date: Fri, 10 Jul 2009 18:27:51 GMT (878kb)

Title: Digital Coherent and Dissipative Quantum Simulations with Rydberg Atoms
Authors: Hendrik Weimer, Markus M\"uller, Igor Lesanovsky, Peter Zoller, Hans
Peter B\"uchler
Categories: quant-ph
Comments: 8 pages, 4 figures
\\
Following Feynman and as elaborated on by Lloyd, a universal quantum
simulator (QS) is a controlled quantum device which reproduces the dynamics of
any other many particle quantum system with short range interactions. This
dynamics can refer to both coherent Hamiltonian and dissipative open system
evolution. We investigate how laser excited Rydberg atoms in large spacing
optical or magnetic lattices can provide an efficient implementation of a
universal QS for spin models involving (high order) n-body interactions. This
includes the simulation of Hamiltonians of exotic spin models involving
n-particle constraints such as the Kitaev toric code, color code, and lattice
gauge theories with spin liquid phases. In addition, it provides the
ingredients for dissipative preparation of entangled states based on
engineering n-particle reservoir couplings. The key basic building blocks of
our architecture are efficient and high-fidelity n-qubit entangling gates via
auxiliary Rydberg atoms, including a possible dissipative time step via optical
pumping. This allows to mimic the time evolution of the system by a sequence of
fast, parallel and high-fidelity n-particle coherent and dissipative Rydberg
gates.
\\ ( http://arxiv.org/abs/0907.1657 , 878kb)
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arXiv:0907.1702
Date: Fri, 10 Jul 2009 01:17:24 GMT (1478kb,D)

Title: Quantum Logic Between Distant Trapped Ions
Authors: S. Olmschenk, D. Hayes, D. N. Matsukevich, P. Maunz, D. L. Moehring,
C. Monroe
Categories: quant-ph
Comments: 59 pages, 19 figures
\\
Trapped atomic ions have proven to be one of the most promising candidates
for the realization of quantum computation due to their long trapping times,
excellent coherence properties, and exquisite control of the internal atomic
states. Integrating ions (quantum memory) with photons (distance link) offers a
unique path to large-scale quantum computation and long-distance quantum
communication. In this article, we present a detailed review of the
experimental implementation of a heralded photon-mediated quantum gate between
remote ions, and the employment of this gate to perform a teleportation
protocol between two ions separated by a distance of about one meter.
\\ ( http://arxiv.org/abs/0907.1702 , 1478kb)
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arXiv:0907.1707
Date: Fri, 10 Jul 2009 01:37:57 GMT (12kb)

Title: The Nature of Time: from a Timeless Hamiltonian Framework to Clock Time
of Metrology
Authors: Enrico Prati
Categories: physics.class-ph
Comments: Fourth Classified at the FQXI Essay Contest "The Nature of Time"
\\
The problem of the Nature of Time is twofold: whether or not time is a
fundamental quantity of Nature, and how does clock time of metrology emerge in
the experimental description of dynamics. This work strongly supports the
fundamental timelessness of Nature. However, the correct view that physics is
described by relations between variables does not address the second problem of
how time does emerge at the macroscopic scale on the ground of a timeless
framework. In this work ordinary Hamiltonian dynamics is recast in a timeless
formalism capable to provide a definition of parameter time on the basis of the
only generalized coordinates, together with the Hamiltonian invariance on
trajectories, and a variational principle. Next, by relaxing the assumption of
periodicity of real clocks to the only cyclicity in the phase space, the second
problem is addressed. Physical systems, if complex enough, can be separated in
a subsystem whose dynamics is described, and another cyclic subsystem which
behaves as a clock. The dynamics of the first is mapped in the states of the
second cyclic subsystem which provides a discrete approximation of the
parameter time. Useful clocks fulfill a stability prescription which guarantees
that dynamics is expressed by simple laws also in terms of metric time as
naturally happens for parameter time. The two ideas provide a unitary framework
capable to account the fundamental timelessness of Nature, and the experimental
evidence of time evolution in macroscopic systems experienced by the observers.
\\ ( http://arxiv.org/abs/0907.1707 , 12kb)
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arXiv:0907.1987
Date: Sat, 11 Jul 2009 20:06:42 GMT (227kb)

Title: Dark soliton oscillations in Bose-Einstein condensates with multi-body
interactions
Authors: A.M. Kamchatnov and M. Salerno
Categories: cond-mat.quant-gas
Comments: submitted in J. Phys. B
\\
We consider the dynamics of dark matter solitons moving through non-uniform
cigar-shaped Bose-Einstein condensates described by the mean field
Gross-Pitaevskii equation with generalized nonlinearities, in the case when the
condition for the modulation stability of the Bose-Einstein condensate is
fulfilled. The analytical expression for the frequency of the oscillations of a
deep dark soliton is derived for nonlinearities which are arbitrary functions
of the density, while specific results are discussed for the physically
relevant case of a cubic-quintic nonlinearity modeling two- and three-body
interactions, respectively. In contrast to the cubic Gross-Pitaevskii equation
for which the frequencies of the oscillations are known to be independent of
background density and interaction strengths, we find that in the presence of a
cubic-quintic nonlinearity an explicit dependence of the oscillations frequency
on the above quantities appears. This dependence gives rise to the possibility
of measuring these quantities directly from the dark soliton dynamics, or to
manage the oscillation via the changes of the scattering lengths by means of
Feshbach resonance. A comparison between analytical results and direct
numerical simulations of the cubic-quintic Gross-Pitaevskii equation shows good
agreement which confirms the validity of our approach.
\\ ( http://arxiv.org/abs/0907.1987 , 227kb)
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arXiv:0907.2193
Date: Mon, 13 Jul 2009 16:04:36 GMT (463kb)

Title: Functional renormalization group approach to the BCS-BEC crossover
Authors: S. Diehl, S. Floerchinger, H. Gies, J. M. Pawlowski, C. Wetterich
Categories: cond-mat.quant-gas
Comments: 28 pages, 12 figures
\\
The phase transition to superfluidity and the BCS-BEC crossover for an
ultracold gas of fermionic atoms is discussed within a functional
renormalization group approach. Non-perturbative flow equations, based on an
exact renormalization group equation, describe the scale dependence of the
flowing or average action. They interpolate continuously from the microphysics
at atomic or molecular distance scales to the macroscopic physics at much
larger length scales, as given by the interparticle distance, the correlation
length, or the size of the experimental probe. We discuss the phase diagram as
a function of the scattering length and the temperature and compute the gap,
the correlation length and the scattering length for molecules. Close to the
critical temperature, we find the expected universal behavior. Our approach
allows for a description of the few-body physics (scattering and molecular
binding) and the many-body physics within the same formalism.
\\ ( http://arxiv.org/abs/0907.2193 , 463kb)
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arXiv:0907.1902
Date: Mon, 13 Jul 2009 17:26:37 GMT (228kb)

Title: Efficient optical quantum state engineering
Authors: Kevin T. McCusker and Paul G. Kwiat
Categories: quant-ph
Comments: 4 pages, 4 figures
\\
We discuss a novel method of efficiently producing multi-photon states using
repeated spontaneous parametric downconversion. Specifically, by attempting
downconversion several times, we can pseudo-deterministically add photons to a
mode, producing various several-photon states. We discuss both expected
performance and experimental limitations.
\\ ( http://arxiv.org/abs/0907.1902 , 228kb)
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arXiv:0907.2217
Date: Mon, 13 Jul 2009 17:26:37 GMT (217kb)

Title: Exact density oscillations in the Tonks-Girardeau gas and their optical
detection
Authors: Mihaly G. Benedict, Csaba Benedek, Attila Czirjak
Categories: quant-ph cond-mat.quant-gas
\\
We construct the exact time dependent density profile for a superposition of
the ground and singly excited states of a harmonically trapped one dimensional
Bose-Einstein condensate in the limit of strongly interacting particles, the
Tonks-Girardeau gas. Results of an off resonant light scattering experiment
probing the system could allow to determine the number of particles contained
in the gas, as well as the coefficients of the superposition.
\\ ( http://arxiv.org/abs/0907.2217 , 217kb)
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arXiv:0907.1926
Date: Fri, 10 Jul 2009 22:43:49 GMT (671kb)

Title: Laser cooling of solids
Authors: Galina Nemova
Categories: physics.optics physics.space-ph
Comments: 26 pages, 6 figures
\\
Parallel to advances in laser cooling of atoms and ions in dilute gas phase,
which has progressed immensely, resulting in physics Nobel prizes in 1997 and
2001, major progress has recently been made in laser cooling of solids. I
compare the physical nature of the laser cooling of atoms and ions with that of
the laser cooling of solids. I point out all advantages of this new and very
promising area of laser physics. Laser cooling of solids (optical
refrigeration) at the present time can be largely divided into three areas:
laser cooling in ion doped glasses or crystals, laser cooling in semiconductors
(bulk or confined, like quantum-well structures), and radiation-balanced
lasers. All three areas, which are equally important and promising, are covered
in the paper.
\\ ( http://arxiv.org/abs/0907.1926 , 671kb)
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arXiv:0907.2245
Date: Wed, 15 Jul 2009 15:18:47 GMT (336kb)

Title: Many-body treatment of the collisional frequency shift in fermionic
atoms
Authors: A. M. Rey, A. V. Gorshkov, C. Rubbo
Categories: physics.atom-ph
Comments: 5 pages, 3 figures
\\
Recent clock experiments have measured density-dependent frequency shifts in
polarized fermionic alkaline-earth atoms using 1S0-3P0 Rabi spectroscopy. Here
we provide a first-principles non-equilibrium theoretical description of the
interaction frequency shifts starting from the microscopic many-body
Hamiltonian. Our formalism describes the dependence of the frequency shift on
excitation inhomogeneity, interactions, and many-body dynamics, provides a
fundamental understanding of the effects of the measurement process, and
explains the observed density shift data. We also propose a method to measure
the second of the two 1S0-3P0 scattering lengths, whose knowledge is essential
for quantum information processing and quantum simulation applications.
\\ ( http://arxiv.org/abs/0907.2245 , 366kb)
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arXiv:0907.2616
Date: Wed, 15 Jul 2009 15:18:47 GMT (209kb)

Title: Casimir force on interacting Bose-Einstein condensate
Authors: Shyamal Biswas, J. K. Bhattacharjee, Dwipesh Majumder, Kush Saha,
Nabajit Chakravarty
Categories: cond-mat.stat-mech cond-mat.quant-gas
Comments: 6 pages, 3 figures
\\
We have presented an analytic theory for the Casimir force on a Bose-Einstein
condensate(BEC) which is confined between two parallel plates. We have
considered short range interactions between the Bose particles of the
condensate. We have obtained the Casimir force from the consideration of the
Dirichlet boundary conditions of the condensate wave function which follows
Gross-Pitaevskii equation. Eventually, our calculation is restricted to zero
temperature.
\\ ( http://arxiv.org/abs/0907.2616 , 209kb)
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arXiv:0907.2453
Date: Wed, 15 Jul 2009 15:18:47 GMT (270kb)

Title: Magnetometry at the quantum limit of sensitivity and beyond
Authors: W. Wasilewski, K. Jensen, H. Krauter, J.J. Renema, and E.S. Polzik
Categories: quant-ph
\\
Ultimate sensitivity of metrology and sensing is defined by the fundamental
principles of quantum physics. The quantum state of a system defines the
magnitude of its quantum fluctuations. The optimal balance between the
information about the system obtained during the measurement and the
destructive back action of the measurement on the measured object is defined by
the laws of quantum mechanics.
Here we demonstrate how the optimal quantum measurement strategy allows us to
achieve the fundamental limit of sensitivity of the oscillating magnetic field
measurement set by the quantum projection noise of atoms. Using techniques
developed for quantum information processing [1-3] we apply an optimal sequence
of state preparation, evolution, and the back-action evading measurement to
achieve the atomic projection noise limited sensitivity of 2.1*$10^{-16}$
Tesla/Hz$^{1/2$} using 1.5*$10^{12}$ room temperature caesium atoms. This
sensitivity is comparable with that of the current state-of-the-art atomic
magnetometer [4], whereas the sensitivity per atom is a hundredfold improvement
over the state of the art. We furthermore demonstrate that under certain
conditions entanglement of atoms generated by a quantum nondemolition
measurement improves the sensitivity of the magnetometer.
\\ ( http://arxiv.org/abs/0907.2453 , 270kb)
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arXiv:0907.2580
Date: Wed, 15 Jul 2009 15:18:47 GMT (5623kb)

Title: Characterization and limits of a cold atom Sagnac interferometer
Authors: A. Gauguet (SYRTE), Benjamin Canuel (SYRTE), Thomas L\'ev\`eque
(SYRTE), Walid Chaibi (ARTEMIS), Arnaud Landragin (SYRTE)
Categories: physics.atom-ph
\\
We present the full evaluation of a cold atom gyroscope based on atom
interferometry. We have performed extensive studies to determine the systematic
errors, scale factor and sensitivity. We demonstrate that the acceleration
noise can be efficiently removed from the rotation signal allowing to reach the
fundamental limit of the quantum projection noise for short term measurements.
The technical limits to the long term sensitivity and accuracy have been
identified, clearing the way for the next generations of ultra-sensitive atom
gyroscopes.
\\ ( http://arxiv.org/abs/0907.2580 , 5623kb)
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arXiv:0907.2687
Date: Wed, 15 Jul 2009 15:18:47 GMT (87kb)

Title: Renormalization of the BCS-BEC crossover by order parameter fluctuations
Authors: Lorenz Bartosch, Peter Kopietz, and Alvaro Ferraz
Categories: cond-mat.quant-gas cond-mat.str-el
Comments: 5 pages, 3 figures
\\
We use the functional renormalization group approach with partial
bosonization in the particle-particle channel to study the effect of order
parameter fluctuations on the BCS-BEC crossover of superfluid fermions in three
dimensions. Our approach is based on a new truncation of the vertex expansion
where the renormalization group flow of bosonic two-point functions is closed
by means of Dyson-Schwinger equations and the superfluid order parameter is
related to the single particle gap via a Ward identity. We explicitly calculate
the chemical potential, the single-particle gap, and the superfluid order
parameter at the unitary point and compare our results with experiments and
previous calculations.
\\ ( http://arxiv.org/abs/0907.2687 , 87kb)
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arXiv:0907.2888
Date: Thu, 16 Jul 2009 17:10:49 GMT (1529kb)

Title: Itinerant Ferromagnetism in a Fermi Gas of Ultracold Atoms
Authors: Gyu-Boong Jo, Ye-Ryoung Lee, Jae-Hoon Choi, Caleb A. Christensen, Tony
H. Kim, Joseph H. Thywissen, David E. Pritchard, and Wolfgang Ketterle
Categories: cond-mat.quant-gas cond-mat.str-el
Comments: 17 pages, 5 figures (incl. Supplemental Material)
\\
Can a gas of spin-up and spin-down fermions become ferromagnetic due to
repulsive interactions? This question which has not yet found a definitive
theoretical answer was addressed in an experiment with an ultracold
two-component Fermi gas. The observation of non-monotonic behavior of lifetime,
kinetic energy, and size for increasing repulsive interactions provides strong
evidence for a phase transition to a ferromagnetic state. It implies that
itinerant ferromagnetism of delocalized fermions is possible without lattice
and band structure and validates the most basic model for ferromagnetism
introduced by Stoner.
\\ ( http://arxiv.org/abs/0907.2888 , 1529kb)
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arXiv:0907.2906
Date: Thu, 16 Jul 2009 19:59:16 GMT (765kb)

Title: Anharmonicity Induced Resonances for Ultracold Atoms and their Detection
Authors: J. P. Kestner, L.-M. Duan
Categories: cond-mat.quant-gas
Comments: 4 pages, 4 figures; comments welcome
\\
When two atoms interact in the presence of an anharmonic potential, such as
an optical lattice, the center of mass motion cannot be separated from the
relative motion. In addition to generating a confinement-induced resonance (or
shifting the position of an existing Feshbach resonance), the external
potential changes the resonance picture qualitatively by introducing new
resonances where molecular excited center of mass states cross the scattering
threshold. We demonstrate the existence of these resonances, give their
quantitative characterization in an optical superlattice, and propose an
experimental scheme to detect them through controlled sweeping of the magnetic
field.
\\ ( http://arxiv.org/abs/0907.2906 , 765kb)
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arXiv:0907.2779
Date: Thu, 16 Jul 2009 08:30:34 GMT (1072kb)

Title: Infrared behavior and spectral function of a Bose superfluid at zero
temperature
Authors: N. Dupuis
Categories: cond-mat.quant-gas
Comments: 23 pages, 11 figures
\\
In a Bose superfluid, the coupling between transverse (phase) and
longitudinal fluctuations leads to a divergence of the longitudinal correlation
function, which is responsible for the occurrence of infrared divergences in
the perturbation theory and the breakdown of the Bogoliubov approximation. We
report a non-perturbative renormalization-group (NPRG) calculation of the
one-particle Green function of an interacting boson system at zero temperature.
We find two regimes separated by a characteristic momentum scale $k_G$
(``Ginzburg'' scale). While the Bogoliubov approximation is valid at large
momenta and energies, $|\p|,|\w|/c\gg k_G$ (with $c$ the velocity of the
Bogoliubov sound mode), in the infrared (hydrodynamic) regime $|\p|,|\w|/c\ll
k_G$ the normal and anomalous self-energies exhibit singularities reflecting
the divergence of the longitudinal correlation function. In particular, we find
that the anomalous self-energy agrees with the Bogoliubov result
$\Sigan(\p,\w)\simeq\const$ at high-energies and behaves as $\Sigan(\p,\w)\sim
(c^2\p^2-\w^2)^{(d-3)/2}$ in the infrared regime (with $d$ the space
dimension), in agreement with the Nepomnyashchii identity $\Sigan(0,0)=0$ and
the predictions of Popov's hydrodynamic theory. We argue that the hydrodynamic
limit of the one-particle Green function is fully determined by the knowledge
of the exponent $3-d$ characterizing the divergence of the longitudinal
susceptibility and the Ward identities associated to gauge and Galilean
invariances. The infrared singularity of $\Sigan(\p,\w)$ leads to a continuum
of excitations (coexisting with the sound mode) which shows up in the
one-particle spectral function.
\\ ( http://arxiv.org/abs/0907.2779 , 1072kb)
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arXiv:0907.1434 (*cross-listing*)
Date: Thu, 9 Jul 2009 07:39:59 GMT (61kb)
Date (revised v2): Thu, 16 Jul 2009 12:46:06 GMT (62kb)

Title: Holographic dual of Cold Trapped Fermions
Authors: Sang-Jin Sin and Ismail Zahed
Categories: hep-th cond-mat.str-el
Comments: 22 page latex, v2:reference added, sec.7's title changed
\\
We study cold fermionic atoms using the holographic principle. We note that
current atomic experiments with massive fermions trapped in a harmonic
potential in the unitarity limit behave as massless fermions thanks to the
Thomas-Fermi approximation. We map the thermodynamics of strongly correlated
massless fermion to that of the charged black hole and study the thermodynamics
and transport properties of cold fermions at strong coupling at finite
temperature and density. The specific heat contains a term linear in $T$ and a
term linear in the density, supporting excitations inside the Fermi surface. At
zero temperature, the energy per particle normalized to the Fermi energy is
$E/NE_F=3\sqrt{\xi}/4$ with $\xi=(N_c/N_f)^{2/3}$. The shear viscosity per
particle is shown to be finite $\eta/n=\xi^{3/4}/4/\sqrt{3}$ as a consequence
of the non-vanishing of the entropy. We show that our holographic results
compare favorably with most of the current atomic data. We suggest that at the
coldest point, trapped atomic measurements offer a unique testing ground for
the status of Nernst theorem for cold but charged black holes.
\\ ( http://arxiv.org/abs/0907.1434 , 62kb)
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arXiv:0907.2720
Date: Wed, 15 Jul 2009 23:28:11 GMT (264kb)

Title: Cavity-QED models of switches for attojoule-scale nanophotonic logic
Authors: Hideo Mabuchi
Categories: quant-ph
Comments: 4 pages, 4 color figures
\\
Quantum optical input-output models are described for a class of optical
switches based on cavity quantum electrodynamics (cavity QED) with a single
multilevel atom (or comparable bound system of charges) coupled simultaneously
to several resonant field modes. A recent limit theorem for quantum stochastic
differential equations is used to show that such models converge to a simple
scattering matrix in a type of strong coupling limit that seems natural for
nanophotonic systems. Numerical integration is used to show that the behavior
of the pre-limit model approximates that of the simple scattering matrix in a
realistic regime for the physical parameters, and that it is possible in the
proposed cavity-QED configuration for low power optical signals to switch
higher-power signals at attojoule energy scales.
\\ ( http://arxiv.org/abs/0907.2720 , 264kb)
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arXiv:0907.2884
Date: Thu, 16 Jul 2009 16:51:17 GMT (942kb)

Title: Decoherence via induced dipole collisions in an ultracold gas
Authors: Anthony R. Gorges, Mathew S. Hamilton, and Jacob L. Roberts
Categories: physics.atom-ph
Comments: 4 page, 4 figures
\\
We have studied the effects of loading $^{87}$Rb into a far off resonant trap
(FORT) in the presence of an ultracold cloud of $^{85}$Rb. The presence of the
$^{85}$Rb resulted in a marked decrease of the $^{87}$Rb load rate. This
decrease is consistent with a decrease in the laser cooling efficiency needed
for effective loading. While many dynamics which disrupt loading efficency
arise when cooling in a dense cloud of atoms (reabsorption, adverse optical
pumping, etc.), the large detuning between the transitions of $^{85}$Rb and
$^{87}$Rb should isolate the isotopes from these effects. For our optical
molasses conditions we calculate that our cooling efficiencies require induced
ground-state coherences. We present data and estimates which are consistent
with heteronuclear long-ranged induced dipole-dipole collisions disrupting
these ground state coherences, leading to a loss of optical trap loading
efficiency.
\\ ( http://arxiv.org/abs/0907.2884 , 942kb)
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The replacements:

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arXiv:0907.0423
replaced with revised version Fri, 10 Jul 2009 14:05:58 GMT (160kb)

Title: Frustrated quantum antiferromagnetism with ultracold bosons in a
triangular lattice
Authors: A. Eckardt, P. Hauke, P. Soltan-Panahi, C. Becker, K. Sengstock, and
M. Lewenstein
Categories: cond-mat.quant-gas cond-mat.other
Comments: 4 pages, 3 figures
\\ ( http://arxiv.org/abs/0907.0423 , 160kb)
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arXiv:0710.0045
replaced with revised version Fri, 10 Jul 2009 22:23:12 GMT (2177kb)

Title: Quantum Entangled Dark Solitons Formed by Ultracold Atoms in Optical
Lattices
Authors: R. V. Mishmash, L. D. Carr
Categories: cond-mat.mes-hall nlin.PS quant-ph
Comments: 4 pages, 4 figures; v3 improves overall discussion and uses better
data for Fig. 2
\\ ( http://arxiv.org/abs/0710.0045 , 2177kb)
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arXiv:0906.2801 (*cross-listing*)
replaced with revised version Sat, 11 Jul 2009 15:07:23 GMT (560kb)

Title: Long-distance entanglement and quantum teleportation in coupled cavity
arrays
Authors: Salvatore M. Giampaolo, Fabrizio Illuminati
Categories: quant-ph cond-mat.other
Comments: 4 pages, 5 figures
\\ ( http://arxiv.org/abs/0906.2801 , 560kb)
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arXiv:0808.3380 (*cross-listing*)
replaced with revised version Mon, 13 Jul 2009 21:59:57 GMT (270kb)

Title: Space-Time Sensors using Multiple-Wave Atomic Levitation
Authors: F. Impens and Ch. J. Bord\'e
Categories: physics.atom-ph cond-mat.other quant-ph
Comments: 5 pages, 4 figures. A few minor changes in the abstract and
introduction
\\ ( http://arxiv.org/abs/0808.3380 , 270kb)
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arXiv:0903.4674
replaced with revised version Wed, 15 Jul 2009 00:12:59 GMT (1622kb,D)

Title: A single structured light beam as an atomic cloud splitter
Authors: B. M. Rodriguez-Lara and R. Jauregui
Categories: quant-ph physics.atom-ph
Comments: 10 pages, 5 figures
\\ ( http://arxiv.org/abs/0903.4674 , 1622kb)
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arXiv:0810.4982
replaced with revised version Thu, 16 Jul 2009 05:27:45 GMT (11kb)

Title: Feasibility of Experimental Realization of Entangled Bose-Einstein
Condensation
Authors: Yu Shi
Categories: cond-mat.other
Comments: 6 pages, published version
Journal-ref: Europhys. Lett. 86, 60008 (2009)
\\ ( http://arxiv.org/abs/0810.4982 , 11kb)
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arXiv:0811.3623
replaced with revised version Thu, 16 Jul 2009 12:37:06 GMT (220kb)

Title: Superfluid-density of the ultra-cold Fermi gas in optical lattices
Authors: T. Paananen
Categories: cond-mat.other
Comments: 21 pages, 9 figures
\\ ( http://arxiv.org/abs/0811.3623 , 220kb)
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Till next time,
Matt.

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Dr M. J. Davis,                      Associate Professor in Physics
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Received on Thu Sep 24 2009 - 15:47:36 EST

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