From: Matthew Davis <mdavis_at_physics.uq.edu.au>

Date: Sat, 05 Sep 2009 20:03:40 +1000

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:

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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.

-- ========================================================================= Dr M. J. Davis, Associate Professor in Physics School of Mathematics and Physics, ph : +61 7 334 69824 The University of Queensland, fax : +61 7 336 51242 Brisbane, QLD 4072, mdavis_at_physics.uq.edu.au Australia. 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 ========================================================================= _______________________________________________ Matts-arxiv mailing list Matts-arxiv_at_lists.sps.uq.edu.auReceived on Thu Sep 24 2009 - 15:47:36 EST

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