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

Date: Tue, 7 Sep 2010 23:30:12 +1000

Date: Tue, 7 Sep 2010 23:30:12 +1000

Dear subscribers,

The last email sent out was unfortunately a re-processing of a previous week's

set of abstracts - so if they seemed familiar, there was a good reason why

(thanks to Aidan Arnold for bringing this to my attention!) This is the

corrected week. I also have 4 weeks worth prepared to send out to you, and will

do so over the course of the next few days.

This week's selection was compiled by a your truly, and contains 47 new

abstracts and 11 replacements.

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arXiv:1006.4579 (*cross-listing*)

Date: Wed, 23 Jun 2010 16:07:28 GMT (61kb)

Title: Dynamics of a quantum quench in an ultra-cold atomic BCS superfluid

Authors: Chih-Chun Chien and Bogdan Damski

Categories: cond-mat.quant-gas cond-mat.supr-con quant-ph

Comments: 4 pages, 3 figures

Report-no: LAUR 10-04106

\\

We study dynamics of an ultra-cold atomic BCS superfluid driven towards the

BCS superfluid-Fermi liquid quantum critical point by a gradual decrease of the

pairing interaction. We analyze how the BCS superfluid falls out of equilibrium

and show that the non-equilibrium gap and Cooper pair size reflect critical

properties of the transition. We observe three stages of evolution: adiabatic

where the Cooper pair size is inversely proportional to the equilibrium gap,

weakly non-equilibrium where it is inversely proportional to the

non-equilibrium gap, and strongly non-equilibrium where it decouples from both

equilibrium and non-equilibrium gap. These phenomena should stimulate future

experimental characterization of non-equilibrium ultra-cold atomic BCS

superfluids.

\\ ( http://arxiv.org/abs/1006.4579 , 61kb)

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arXiv:1007.0281 (*cross-listing*)

Date: Fri, 2 Jul 2010 00:23:43 GMT (2163kb)

Title: Phase fluctuations in anisotropic Bose condensates: from cigars to rings

Authors: L. Mathey, A. Ramanathan, K. C. Wright, S. R. Muniz, W. D. Phillips

and Charles W. Clark

Categories: cond-mat.quant-gas quant-ph

Comments: 9 pages, 5 figures

\\

We study the phase-fluctuating condensate regime of ultra-cold atoms trapped

in a ring-shaped trap geometry, which has been realized in recent experiments.

We first consider a simplified box geometry, in which we identify the

conditions to create a state that is dominated by thermal phase-fluctuations,

and then explore the experimental ring geometry. In both cases we demonstrate

that the requirement for strong phase fluctuations can be expressed in terms of

the total number of atoms and the geometric length scales of the trap only. For

the ring-shaped trap we discuss the zero temperature limit in which a

condensate is realized where the phase is fluctuating due to interactions and

quantum fluctuations. We also address possible ways of detecting the phase

fluctuating regime in ring condensates.

\\ ( http://arxiv.org/abs/1007.0281 , 2163kb)

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arXiv:1007.0294

Date: Fri, 2 Jul 2010 05:04:58 GMT (1493kb,D)

Title: Synthetic magnetic fields for ultracold neutral atoms

Authors: Yu-Ju Lin, Rob L. Compton, Karina J. Garcia, James V. Porto, Ian B.

Spielman

Categories: cond-mat.quant-gas

Journal-ref: Nature 462, 628 (2009)

\\

Neutral atomic Bose condensates and degenerate Fermi gases have been used to

realize important many-body phenomena in their most simple and essential forms,

without many of the complexities usually associated with material systems.

However, the charge neutrality of these systems presents an apparent limitation

- a wide range of intriguing phenomena arise from the Lorentz force for charged

particles in a magnetic field, such as the fractional quantum Hall states in

two-dimensional electron systems. The limitation can be circumvented by

exploiting the equivalence of the Lorentz force and the Coriolis force to

create synthetic magnetic fields in rotating neutral systems. This was

demonstrated by the appearance of quantized vortices in pioneering experiments

on rotating quantum gases, a hallmark of superfluids or superconductors in a

magnetic field. However, because of technical issues limiting the maximum

rotation velocity, the metastable nature of the rotating state and the

difficulty of applying stable rotating optical lattices, rotational approaches

are not able to reach the large fields required for quantum Hall physics. Here,

we experimentally realize an optically synthesized magnetic field for ultracold

neutral atoms, made evident from the appearance of vortices in our

Bose-Einstein condensate. Our approach uses a spatially-dependent optical

coupling between internal states of the atoms, yielding a Berry's phase

sufficient to create large synthetic magnetic fields, and is not subject to the

limitations of rotating systems; with a suitable lattice configuration, it

should be possible to reach the quantum Hall regime, potentially enabling

studies of topological quantum computation.

\\ ( http://arxiv.org/abs/1007.0294 , 1493kb)

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arXiv:1007.0335

Date: Fri, 2 Jul 2010 10:40:25 GMT (461kb)

Title: Carnot Theorem for nonequilibrium reservoirs

Authors: Simone De Liberato and Masahito Ueda

Categories: quant-ph cond-mat.stat-mech

\\

The Carnot theorem poses a fundamental limit on the maximal efficiency

achievable from an engine that works between two reservoirs at thermal

equilibrium. In this paper we extend this result to the case of arbitrary

nonequilibrium reservoirs, by proving that a single nonequilibrium reservoir is

formally equivalent to multiple equilibrium ones. We then apply our theory to

the case of quantum coherent reservoirs, testing our results against previous

theoretical calculations and predicting the possibility to realize a quantum

coherent engine working at unit efficiency.

\\ ( http://arxiv.org/abs/1007.0335 , 461kb)

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arXiv:1007.0397

Date: Fri, 2 Jul 2010 16:46:18 GMT (2399kb)

Title: Deterministic entanglement of two neutral atoms via Rydberg blockade

Authors: X. L. Zhang, L. Isenhower, A. T. Gill, T. G. Walker, and M. Saffman

Categories: quant-ph physics.atom-ph

Comments: 4 figures

\\

We demonstrate the first deterministic entanglement of two individually

addressed neutral atoms using a Rydberg blockade mediated controlled-NOT gate.

Parity oscillation measurements reveal an entanglement fidelity of

$F=0.58\pm0.04$, which is above the entanglement threshold of $F=0.5$, without

any correction for atom loss, and $F=0.71\pm0.05$ after correcting for

background collisional losses. The fidelity results are shown to be in good

agreement with a detailed error model.

\\ ( http://arxiv.org/abs/1007.0397 , 2399kb)

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arXiv:1007.0400

Date: Fri, 2 Jul 2010 17:06:35 GMT (185kb)

Title: Effect of spatial inhomogeneity on the mapping between strongly

interacting fermions and weakly interacting spins

Authors: Vivian V. Fran\c{c}a and Klaus Capelle

Categories: cond-mat.str-el

Comments: 7 pages, 6 figures

\\

A combined analytical and numerical study is performed of the mapping between

strongly interacting fermions and weakly interacting spins, in the framework of

the Hubbard, t-J and Heisenberg models. While for spatially homogeneous models

in the thermodynamic limit the mapping is thoroughly understood, we here focus

on aspects that become relevant in spatially inhomogeneous situations, such as

the effect of boundaries, impurities, superlattices and interfaces. We consider

parameter regimes that are relevant for traditional applications of these

models, such as electrons in cuprates and manganites, and for more recent

applications to atoms in optical lattices. The rate of the mapping as a

function of the interaction strength is determined from the Bethe-Ansatz for

infinite systems and from numerical diagonalization for finite systems. We show

analytically that if translational symmetry is broken through the presence of

impurities, the mapping persists and is, in a certain sense, as local as

possible, provided the spin-spin interaction between two sites of the

Heisenberg model is calculated from the harmonic mean of the onsite Coulomb

interaction on adjacent sites of the Hubbard model. Numerical calculations

corroborate these findings also in interfaces and superlattices, where

analytical calculations are more complicated.

\\ ( http://arxiv.org/abs/1007.0400 , 185kb)

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arXiv:1007.0403

Date: Fri, 2 Jul 2010 17:12:02 GMT (1344kb)

Title: A continuous-variable formalism for the Faraday atom-light interface

Authors: Julia Stasi\'nska, Simone Paganelli, Carles Rod\'o and Anna Sanpera

Categories: quant-ph

\\

Quantum interfaces between polarized atomic ensembles and coherent states of

light, applied recently to manipulate bipartite and multipartite entanglement,

are revisited by means of a continuous-variable formalism. The explicit use of

the continuous-variable formalism facilitates significantly the analysis of

entanglement between different modes, reducing it to the study of the

properties of a final covariance matrix which can be found analytically.

Furthermore, it allows to study matter-light interfaces for mixed states,

adapting the formalism to the experimental situations in which the initial

prepared Gaussian states are, unavoidably, affected by a certain amount of

noise. A multipartite scenario, leading to the generation of macroscopic

cluster states is presented and analyzed in detail within this formalism.

\\ ( http://arxiv.org/abs/1007.0403 , 1344kb)

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arXiv:1007.0458 (*cross-listing*)

Date: Fri, 2 Jul 2010 23:17:59 GMT (743kb)

Title: External field control of collective spin excitations in an optical

lattice of $^2\Sigma$ molecules

Authors: Jes\'us P\'erez-R\'ios, Felipe Herrera and Roman V. Krems

Categories: physics.chem-ph physics.atom-ph quant-ph

\\

We show that an ensemble of $^2\Sigma$ molecules in the rotationally ground

state trapped on an optical lattice exhibits collective spin excitations that

can be controlled by applying superimposed electric and magnetic fields. In

particular, we show that the lowest energy excitation of the molecular ensemble

at certain combinations of electric and magnetic fields leads to the formation

of a magnetic Frenkel exciton. The exciton bandwidth can be tuned by varying

the electric or magnetic fields. We show that the exciton states can be

localized by creating vacancies in the optical lattice. The localization

patterns of the magnetic exciton states are sensitive to the number and

distribution of vacancies, which can be exploited for engineering many-body

entangled spin states. We consider the dynamics of magnetic exciton wavepackets

and show that the spin excitation transfer between molecules in an optical

lattice can be accelerated or slowed down by tuning an external magnetic or

electric field.

\\ ( http://arxiv.org/abs/1007.0458 , 743kb)

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arXiv:1007.0462 (*cross-listing*)

Date: Sat, 3 Jul 2010 00:18:48 GMT (14kb)

Title: Blackbody radiation shift in 87Rb frequency standard

Authors: M. S. Safronova, Dansha Jiang, and U. I. Safronova

Categories: physics.atom-ph quant-ph

Comments: 7 pages

\\

The operation of atomic clocks is generally carried out at room temperature,

whereas the definition of the second refers to the clock transition in an atom

at absolute zero. This implies that the clock transition frequency should be

corrected in practice for the effect of finite temperature of which the leading

contributor is the blackbody radiation (BBR) shift. Experimental measurements

of the BBR shifts are difficult. In this work, we have calculated the blackbody

radiation shift of the ground-state hyperfine microwave transition in 87Rb

using the relativistic all-order method and carried out detailed evaluation of

the accuracy of our final value. Particular care is taken to accurately account

for the contributions from highly-excited states. Our predicted value for the

Stark coefficient, k_S=-1.240(4)\times 10^{-10}\text{Hz/(V/m)}^{2} is three

times more accurate than the previous calculation [1].

\\ ( http://arxiv.org/abs/1007.0462 , 14kb)

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arXiv:1007.0469

Date: Sat, 3 Jul 2010 05:52:04 GMT (376kb,D)

Title: Collisional properties of cold spin-polarized nitrogen gas: theory,

experiment, and prospects as a sympathetic coolant for trapped atoms and

molecules

Authors: T. V. Tscherbul, J. Klos, A. Dalgarno, B. Zygelman, Z. Pavlovic, M. T.

Hummon, H-I Lu, E. Tsikata, J. M. Doyle

Categories: physics.atom-ph

Comments: 46 pages, 17 figures, 3 tables

\\

We report a combined experimental and theoretical study of collision-induced

dipolar relaxation in a cold spin-polarized gas of atomic nitrogen (N). We use

buffer gas cooling to create trapped samples of 14N and 15N atoms with

densities 5+/-2 x 10^{12} cm-3 and measure their magnetic relaxation rates at

milli-Kelvin temperatures. Rigorous quantum scattering calculations based on

accurate ab initio interaction potentials for the 7Sigma_u electronic state of

N2 demonstrate that dipolar relaxation in N + N collisions occurs at a slow

rate of ~10^{-13} cm3/s over a wide range of temperatures (1 mK to 1 K) and

magnetic fields (10 mT to 2 T). The calculated dipolar relaxation rates are

insensitive to small variations of the interaction potential and to the

magnitude of the spin-exchange interaction, enabling the accurate calibration

of the measured N atom density. We find consistency between the calculated and

experimentally determined rates. Our results suggest that N atoms are promising

candidates for future experiments on sympathetic cooling of molecules.

\\ ( http://arxiv.org/abs/1007.0469 , 376kb)

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arXiv:1007.0480 (*cross-listing*)

Date: Sat, 3 Jul 2010 08:32:41 GMT (777kb)

Title: Diffusive Decay of the Vortex Tangle and Kolmogorov turbulence in

quantum fluids

Authors: Sergey K. Nemirovskii, L.P. Kondaurova

Categories: cond-mat.other physics.flu-dyn quant-ph

Comments: The work was presented at SUR 2010, submitted in JLTP

\\

The idea that chaotic set of quantum vortices can mimic classical turbulence,

or at least reproduce many main features, is currently actively being

developed. Appreciating significance of the challenging problem of the

classical turbulence it can be expressed that the idea to study it in terms of

quantized line is indeed very important and may be regarded as a breakthrough.

For this reason, this theory should be carefully scrutinized. One of the basic

arguments supporting this point of view is the fact that vortex tangle decays

at zero temperature, when the apparent mechanism of dissipation (mutual

friction) is absent. Since the all possible mechanisms of dissipation of the

vortex energy, discussed in the literature, are related to the small scales, it

is natural to suggest that the Kolmogorov cascade takes the place with the flow

of the energy, just as in the classical turbulence. In a series of recent

experiment attenuation of vortex line density was observed and authors

attribute this decay to the properties of the Kolmogorov turbulence. In the

present work we discuss alternative possibility of decay of the vortex tangle,

which is not related to dissipation at small scales. This mechanism is just the

diffusive like spreading of the vortex tangle. We discuss a number of the key

experiments, considering them both from the point of view of alternative

explanation and of the theory of Kolmogorov turbulence in quantum fluids.

\\ ( http://arxiv.org/abs/1007.0480 , 777kb)

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arXiv:1007.0506

Date: Sat, 3 Jul 2010 17:57:28 GMT (153kb)

Title: Matter-wave localization in a random potential

Authors: Yongshan Cheng and S. K. Adhikari

Categories: cond-mat.quant-gas

\\

By numerical and variational solution of the Gross-Pitaevskii equation, we

studied the localization of a noninteracting and weakly-interacting

Bose-Einstein condensate (BEC) in a disordered cold atom lattice and a speckle

potential. In the case of a single BEC fragment, the variational analysis

produced good results. For a weakly disordered potential, the localized BECs

are found to have an exponential tail as in weak Anderson localization. We also

investigated the expansion of a noninteracting BEC in these potential. We find

that the BEC will be locked in an appropriate localized state after an initial

expansion and will execute breathing oscillation around a mean shape when a BEC

at equilibrium in a harmonic trap is suddenly released into a disorder

potential.

\\ ( http://arxiv.org/abs/1007.0506 , 153kb)

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arXiv:1007.0565

Date: Sun, 4 Jul 2010 16:05:31 GMT (560kb,D)

Title: Optomechanically induced transparency

Authors: S. Weis, R. Riviere, S. Deleglise, E. Gavartin, O. Arcizet, A.

Schliesser, T. J. Kippenberg

Categories: quant-ph

\\

Coherent interaction of laser radiation with multilevel atoms and molecules

can lead to quantum interference in the electronic excitation pathways. A

prominent example observed in atomic three-level-systems is the phenomenon of

electromagnetically induced transparency (EIT), in which a control laser

induces a narrow spectral transparency window for a weak probe laser beam. The

concomitant rapid variation of the refractive index in this spectral window can

give rise to dramatic reduction of the group velocity of a propagating pulse of

probe light. Dynamic control of EIT via the control laser enables even a

complete stop, that is, storage, of probe light pulses in the atomic medium.

Here, we demonstrate optomechanically induced transparency (OMIT)--formally

equivalent to EIT--in a cavity optomechanical system operating in the resolved

sideband regime. A control laser tuned to the lower motional sideband of the

cavity resonance induces a dipole-like interaction of optical and mechanical

degrees of freedom. Under these conditions, the destructive interference of

excitation pathways for an intracavity probe field gives rise to a window of

transparency when a two-photon resonance condition is met. As a salient feature

of EIT, the power of the control laser determines the width and depth of the

probe transparency window. OMIT could therefore provide a new approach for

delaying, slowing and storing light pulses in long-lived mechanical excitations

of optomechanical systems, whose optical and mechanical properties can be

tailored in almost arbitrary ways in the micro- and nano-optomechanical

platforms developed to date.

\\ ( http://arxiv.org/abs/1007.0565 , 560kb)

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arXiv:1007.0574

Date: Sun, 4 Jul 2010 17:57:23 GMT (470kb,D)

Title: Quantum Enhancement of the Zero-Area Sagnac Interferometer Topology for

Gravitational Wave Detection

Authors: Tobias Eberle, Sebastian Steinlechner, J\"oran Bauchrowitz, Vitus

H\"andchen, Henning Vahlbruch, Moritz Mehmet, Helge M\"uller-Ebhardt, Roman

Schnabel

Categories: quant-ph

Comments: 4 pages, 4 figures

Journal-ref: Phys. Rev. Lett. 104, 251102 (2010)

DOI: 10.1103/PhysRevLett.104.251102

\\

Only a few years ago, it was realized that the zero-area Sagnac

interferometer topology is able to perform quantum nondemolition measurements

of position changes of a mechanical oscillator. Here, we experimentally show

that such an interferometer can also be efficiently enhanced by squeezed light.

We achieved a nonclassical sensitivity improvement of up to 8.2 dB, limited by

optical loss inside our interferometer. Measurements performed directly on our

squeezed-light laser output revealed squeezing of 12.7 dB. We show that the

sensitivity of a squeezed-light enhanced Sagnac interferometer can surpass the

standard quantum limit for a broad spectrum of signal frequencies without the

need for filter cavities as required for Michelson interferometers. The Sagnac

topology is therefore a powerful option for future gravitational-wave

detectors, such as the Einstein Telescope, whose design is currently being

studied.

\\ ( http://arxiv.org/abs/1007.0574 , 470kb)

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arXiv:1007.0645

Date: Mon, 5 Jul 2010 09:37:50 GMT (544kb)

Title: Fluctuation induced drift in a gravitationally tilted optical lattice

Authors: M. Zelan, H. Hagman, K. Karlsson, C. M. Dion, A. Kastberg

Categories: physics.atom-ph cond-mat.stat-mech

\\

Experimental and theoretical studies are made of Brownian particles trapped

in a periodic potential, which is very slightly tilted due to gravity. In the

presence of fluctuations, these will trigger a measurable average drift along

the direction of the tilt. The magnitude of the drift varies with the ratio

between the bias force and the trapping potential. This can be closely compared

to a theoretical model system, based on a Fokker-Planck-equation formalism. We

show that the level of control and measurement precision we have in our system,

which is based on cold atoms trapped in a 3D dissipative optical lattice, makes

the experimental setup suitable as a testbed for fundamental statistical

physics. We simulate the system with a very simplified and general classical

model, as well as with an elaborate semi-classical Monte-Carlo simulation. In

both cases, we achieve good qualitative agreement with experimental data.

\\ ( http://arxiv.org/abs/1007.0645 , 544kb)

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arXiv:1007.0650

Date: Mon, 5 Jul 2010 09:48:15 GMT (555kb,D)

Title: Bose-Einstein Condensates in Non-abelian Gauge Fields

Authors: Tin-Lun Ho and Shizhong Zhang

Categories: cond-mat.quant-gas

\\

The recent success of the NIST group in generating abelian gauge field in

cold atoms has created opportunities to simulate electronic transports in

solids using atomic gases. Very recently, the NIST group has also announced in

a DARPA Meeting the creation of non-abelian gauge fields in a pseudo spin-1/2

Bose gas. While there have been considerable theoretical activities in

synthetic gauge fields, non-abelian fields have not been generated until now.

Here, we show that in a non-abelian gauge field, a spinor condensate will

develop a spontaneous stripe structure in each spin component, reflecting a

ground state made up of two non-orthogonal dressed states with different

momenta. Depending on interactions, this ground state can reduce back to a

single dressed state. These momentum carrying stripes are the {\em macroscopic}

bosonic counterpart of the spin-orbit phenomena in fermions that are being

actively studied in electron physics today.

\\ ( http://arxiv.org/abs/1007.0650 , 555kb)

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arXiv:1007.0679

Date: Mon, 5 Jul 2010 13:44:12 GMT (4597kb)

Title: A portable laser system for high precision atom interferometry

experiments

Authors: Malte Schmidt, Marco Prevedelli, Antonio Giorgini, Guglielmo M. Tino,

Achim Peters

Categories: physics.atom-ph

Comments: 7 pages, 11 figures; to be published

\\

We present a modular rack-mounted laser system for the cooling and

manipulation of neutral rubidium atoms which has been developed for the

portable gravimeter GAIN, an atom interferometer that will be capable of

performing high precision gravity measurements directly at sites of geophysical

interest. This laser system is designed to be compact, mobile and robust, yet

it still offers improvements over many conventional laboratory-based laser

systems. Our system is contained in a standard 19" rack and emits light at five

different wavelengths simultaneously on up to 12 fibre ports at a total output

power of 800 mW. These wavelengths can be changed and switched between ports in

less than a microsecond. The setup includes two phase-locked Raman lasers with

a phase noise spectral density of less than 1 \mu rad/sqrt(Hz) in the frequency

range in which our gravimeter is most sensitive to noise. We characterize this

laser system and evaluate the performance limits it imposes on an

interferometer.

\\ ( http://arxiv.org/abs/1007.0679 , 4597kb)

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arXiv:1007.0685

Date: Mon, 5 Jul 2010 14:11:55 GMT (41kb)

Title: Reference data for phase diagrams of triangular and hexagonal bosonic

lattices

Authors: Niklas Teichmann, Dennis Hinrichs, Martin Holthaus

Categories: cond-mat.quant-gas

Comments: 6 pages, 5 figures, accepted for publication in EPL

\\

We investigate systems of bosonic particles at zero temperature in triangular

and hexagonal optical lattice potentials in the framework of the Bose-Hubbard

model. Employing the process-chain approach, we obtain accurate values for the

boundaries between the Mott insulating phase and the superfluid phase. These

results can serve as reference data for both other approximation schemes and

upcoming experiments. Since arbitrary integer filling factors g are amenable to

our technique, we are able to monitor the behavior of the critical hopping

parameters with increasing filling. We also demonstrate that the g-dependence

of these exact parameters is described almost perfectly by a scaling relation

inferred from the mean-field approximation.

\\ ( http://arxiv.org/abs/1007.0685 , 41kb)

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arXiv:1007.0694

Date: Mon, 5 Jul 2010 14:58:36 GMT (1000kb)

Title: Quantum jumps induced by matter-wave fluctuations

Authors: J. M. Torres, M. Bienert, S. Zippilli, and G. Morigi

Categories: quant-ph

\\

We theoretically study the occurrence of quantum jumps in the resonance

fluorescence of a trapped atom. Here, the atom is laser cooled in a

configuration of level such that the occurrence of a quantum jump is associated

to a change of the vibrational center-of-mass motion by one phonon. The

statistics of the occurrence of the dark fluorescence period is studied as a

function of the physical parameters and the corresponding features in the

spectrum of resonance fluorescence are identified. We discuss the information

which can be extracted on the atomic motion from the observation of a quantum

jump in the considered setup.

\\ ( http://arxiv.org/abs/1007.0694 , 1000kb)

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arXiv:1007.0703 (*cross-listing*)

Date: Mon, 5 Jul 2010 15:26:47 GMT (18kb)

Title: Phase Estimation With Interfering Bose-Condensed Atomic Clouds

Authors: Jan Chwedenczuk, Francesco Piazza and Augusto Smerzi

Categories: cond-mat.quant-gas quant-ph

Comments: 4 pages, 2 figures

\\

We investigate how to estimate from atom-position measurements the relative

phase of two Bose-Einstein condensates released from a double-well potential.

We demonstrate that the phase estimation sensitivity via the fit of the average

density to the interference pattern is fundamentally bounded by shot noise.

This bound can be overcome by estimating the phase from the measurement of

$\sqrt N$ (or higher) correlation function. The optimal estimation strategy

requires the measurement of the $N$-th order correlation function. We also

demonstrate that a second estimation method -- based on the detection of the

center of mass of the interference pattern -- provides sub shot-noise

sensitivity. Yet, the implementation of both protocols might be experimentally

challenging.

\\ ( http://arxiv.org/abs/1007.0703 , 18kb)

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arXiv:1007.0782 (*cross-listing*)

Date: Mon, 5 Jul 2010 23:11:03 GMT (1048kb,D)

Title: Spin-charge-density wave in a squircle-like Fermi surface for ultracold

atoms

Authors: D. Makogon and I. B. Spielman and C. Morais Smith

Categories: cond-mat.quant-gas cond-mat.str-el physics.atom-ph

Comments: 4.2 pages, 2 figures

\\

We derive and discuss an experimentally realistic model describing ultracold

atoms in an optical lattice including a commensurate, but staggered, Zeeman

field. The resulting band structure is quite exotic; fermions in the third band

have an unusual rounded picture-frame Fermi surface (essentially two concentric

squircles), leading to imperfect nesting. We develop a generalized

SO(3,1)xSO(3,1) theory describing the spin and charge degrees of freedom

simultaneously, and show that the system can develop a coupled

spin-charge-density wave order. This ordering is absent in studies of the

Hubbard model that treat spin and charge density separately.

\\ ( http://arxiv.org/abs/1007.0782 , 1048kb)

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arXiv:1007.0792

Date: Tue, 6 Jul 2010 01:36:57 GMT (608kb)

Title: Exact few-body results for strongly correlated quantum gases in two

dimensions

Authors: Xia-Ji Liu, Hui Hu and Peter D. Drummond

Categories: cond-mat.quant-gas

Comments: 11 pages, 6 figures

\\

The study of strongly correlated quantum gases in two dimensions has

important ramifications for understanding many intriguing pheomena in solid

materials, such as high-$T_{c}$ superconductivity and the fractional quantum

Hall effect. However, theoretical methods are plagued by the existence of

significant quantum fluctuations. Here, we present two- and three-body exact

solutions for both fermions and bosons trapped in a two-dimensional harmonic

potential, with an arbitrary $s$-wave scattering length. These few-particle

solutions link in a natural way to the high-temperature properties of

many-particle systems via a quantum virial expansion. As a concrete example,

using the energy spectrum of few fermions, we calculate the second and third

virial coefficients of a strongly interacting Fermi gas in two dimensions, and

consequently investigate its high-temperature thermodynamics. Our thermodynamic

results may be useful for ongoing experiments on two-dimensional Fermi gases.

These exact results also provide an unbiased benchmark for quantum Monte Carlo

simulations of two-dimensional Fermi gases at high temperatures.

\\ ( http://arxiv.org/abs/1007.0792 , 608kb)

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arXiv:1007.0794 (*cross-listing*)

Date: Tue, 6 Jul 2010 02:05:50 GMT (1479kb)

Title: Atomic spatial coherence with spontaneous emission in a strong coupling

cavity

Authors: Zhen Fang, Rui Guo, Xiaoji Zhou, Xuzong Chen

Categories: physics.atom-ph cond-mat.quant-gas quant-ph

Comments: 4 pages, 5 figures, accepted by PRA

\\

The role of spontaneous emission in the interaction between a two-level atom

and a pumped micro-cavity in the strong coupling regime is discussed in this

paper. Especially, using a quantum Monte-Carlo simulation, we investigate

atomic spatial coherence. It is found that atomic spontaneous emission destroys

the coherence between neighboring lattice sites, while the cavity decay does

not. Furthermore, our computation of the spatial coherence function shows that

the in-site locality is little affected by the cavity decay, but greatly

depends on the cavity pump amplitude.

\\ ( http://arxiv.org/abs/1007.0794 , 1479kb)

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arXiv:1007.0840 (*cross-listing*)

Date: Tue, 6 Jul 2010 09:20:01 GMT (917kb)

Title: Entanglement Spectrum Identifying Transition from Vortex Liquid to

Vortex Lattice

Authors: Zhao Liu, Hong-Li Guo, Vlatko Vedral and Heng Fan

Categories: cond-mat.quant-gas quant-ph

Comments: 4 pages, 4 figures, comments are welcome

\\

We use entanglement to investigate the transition from vortex liquid phase to

vortex lattice phase in weakly interacting rotating Bose-Einstein condensate on

the torus geometry. Ground state entanglement spectrum is analyzed to

distinguish these two different phases. The low-lying part of ground state

entanglement spectrum, as well as the behavior of its lowest level change

clearly when the transition occurs. We also show that the decrease of

entanglement between particles can be regarded as a signal of the transition.

\\ ( http://arxiv.org/abs/1007.0840 , 917kb)

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arXiv:1007.0884

Date: Tue, 6 Jul 2010 13:16:45 GMT (89kb)

Title: Coherently enhanced Raman scattering in atomic vapor

Authors: Chun-Hua Yuan, L. Q. Chen, Jietai Jing, Z. Y. Ou, Weiping Zhang

Categories: quant-ph

Comments: 7 pages, 4 figures, submitted to Phys. Rev. A

\\

We present a scheme to obtain the coherently enhanced Raman scattering in

atomic vapor which is induced by a spin wave initially written by a weak write

laser. The enhancement of Raman scattering is dependent on the number and the

spatial distribution of the flipped atoms generated by the weak write laser.

Such an enhanced Raman scattering may have practical applications in quantum

information, nonlinear optics and laser spectroscopy because of its simplicity.

\\ ( http://arxiv.org/abs/1007.0884 , 89kb)

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\\

arXiv:1007.0886

Date: Tue, 6 Jul 2010 13:23:15 GMT (1386kb,D)

Title: Asymptotic Bound-state Model for Feshbach Resonances

Authors: T.G. Tiecke and M.R. Goosen and J.T.M. Walraven and S.J.J.M.F.

Kokkelmans

Categories: cond-mat.quant-gas

Comments: 13 pages, 8 figures

\\

We present an Asymptotic Bound-state Model which can be used to accurately

describe all Feshbach resonance positions and widths in a two-body system. With

this model we determine the coupled bound states of a particular two-body

system. The model is based on analytic properties of the two-body Hamiltonian,

and on asymptotic properties of uncoupled bound states in the interaction

potentials. In its most simple version, the only necessary parameters are the

least bound state energies and actual potentials are not used. The complexity

of the model can be stepwise increased by introducing threshold effects,

multiple vibrational levels and additional potential parameters. The model is

extensively tested on the 6Li-40K system and additional calculations on the

40K-87Rb system are presented.

\\ ( http://arxiv.org/abs/1007.0886 , 1386kb)

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\\

arXiv:1007.0913 (*cross-listing*)

Date: Tue, 6 Jul 2010 15:05:52 GMT (261kb)

Title: Quantum phase transitions in an interacting atom-molecule boson model

Authors: Gilberto Santos, Angela Foerster, Jon Links, Eduardo Mattei, Silvio R.

Dahmen

Categories: cond-mat.quant-gas quant-ph

Comments: 6 pages, 10 figures

Journal-ref: Physical Review A, 81, 063621 (2010)

DOI: 10.1103/PhysRevA.81.063621

\\

We study the quantum phase transitions of a model that describes the

interconversion of interacting bosonic atoms and molecules. Using a classical

analysis, we identify a threshold coupling line separating a molecular phase

and a mixed phase. Through studies of the energy gap, von Neumann entanglement

entropy, and fidelity, we give evidence that this line is associated to a

boundary line in the ground-state phase diagram of the quantum system.

\\ ( http://arxiv.org/abs/1007.0913 , 261kb)

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\\

arXiv:1007.0922 (*cross-listing*)

Date: Tue, 6 Jul 2010 15:21:08 GMT (1760kb,D)

Title: Atom-light crystallization of BECs in multimode cavities: Nonequilibrium

classical and quantum phase transitions, emergent lattices, supersolidity,

and frustration

Authors: Sarang Gopalakrishnan, Benjamin L. Lev, Paul M. Goldbart

Categories: cond-mat.quant-gas quant-ph

Comments: 34 pages, 13 figures; follow up to Nat. Phys. 5, 845 (2009)

\\

The self-organization of a Bose-Einstein condensate in a transversely pumped

optical cavity is a process akin to crystallization: when pumped by a laser of

sufficient intensity, the coupled matter and light fields evolve,

spontaneously, into a spatially modulated pattern, or crystal, whose lattice

structure is dictated by the geometry of the cavity. In cavities having

multiple degenerate modes, the quasi-continuum of possible lattice

arrangements, and the continuous symmetry breaking associated with the adoption

of a particular lattice arrangement, give rise to phenomena such as phonons,

defects, and frustration, which have hitherto been unexplored in ultracold

atomic settings. The present work develops a nonequilibrium field-theoretic

approach to explore the self-organization of a BEC in a pumped, lossy optical

cavity. We find that the transition is well described, in the regime of primary

interest, by an effective equilibrium theory. At nonzero temperatures, the

self-organization occurs via a fluctuation-driven first-order phase transition

of the Brazovskii class; this transition persists to zero temperature, and

crosses over into a quantum phase transition of a new universality class. We

make further use of our field-theoretic description to investigate the role of

nonequilibrium fluctuations on the self-organization transition, as well as to

explore the nucleation of ordered-phase droplets, the nature and energetics of

topological defects, supersolidity in the ordered phase, and the possibility of

frustration controlled by the cavity geometry. In addition, we discuss the

range of experimental parameters for which we expect the phenomena described

here to be observable, along with possible schemes for detecting ordering and

fluctuations via either atomic correlations or the correlations of the light

emitted from the cavity.

\\ ( http://arxiv.org/abs/1007.0922 , 1760kb)

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\\

arXiv:1007.0946

Date: Tue, 6 Jul 2010 16:38:10 GMT (502kb)

Title: Story of a journey: Rutherford to the Large Hadron Collider and onwards

Authors: Rohini M. Godbole

Categories: physics.pop-ph hep-ph

Comments: 30 pages, 6 figures, LaTeX

\\

In this article, I set out arguments why the Large Hadron Collider (LHC) :

the machine and the experiments with it, are a watershed for particle physics.

I give a historical perspective of the essential link between development of

particle accelerators and that in our knowledge of the laws governing

interactions among the fundamental particles, showing how this journey has

reached destination LHC. I explain how the decisions for the LHC design; the

energy and number of particles in the beam, were arrived at. I will end by

discussing the LHC physics agenda and the time line in which the particle

physicists hope to achieve it.

\\ ( http://arxiv.org/abs/1007.0946 , 502kb)

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\\

arXiv:1007.0985

Date: Tue, 6 Jul 2010 19:48:43 GMT (736kb,D)

Title: Mapping the spatial distribution of entanglement in optical lattices

Authors: Emilio Alba, Geza Toth and Juan Jose Garcia-Ripoll

Categories: quant-ph

Comments: 2 figures, 4 pages

\\

We study the entangled states that can be generated using two species of

atoms trapped in independently movable, two-dimensional optical lattices. We

show that using two sets of measurements it is possible to measure a set of

entanglement witness operators distributed over arbitrarily large regions of

the lattice, and use these witnesses to produce two-dimensional plots of the

entanglement content of these states. We also discuss the influence of noise on

the states and on the witnesses, as well as connections to ongoing experiments.

\\ ( http://arxiv.org/abs/1007.0985 , 736kb)

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\\

arXiv:1007.1029

Date: Wed, 7 Jul 2010 01:04:36 GMT (490kb,D)

Title: Quantum Phase Transitions in quasi-one dimensional systems

Authors: Thierry Giamarchi

Categories: cond-mat.str-el

Comments: Chapter of the book: Understanding Quantum Phase Transitions, ed.

Lincoln D. Carr (CRC Press / Taylor&Francis, 2010, to appear)

\\

I review in this chapter several classes of quantum phase transitions that

occur in quasi-one dimensional systems. I start by examining the simple case of

coupled spin chains and ladders, then move to the case of bosons, and finally

deal with the more complicated and still largely open case of fermions.

\\ ( http://arxiv.org/abs/1007.1029 , 490kb)

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\\

arXiv:1007.1030

Date: Wed, 7 Jul 2010 01:05:46 GMT (849kb,D)

Title: Interactions in Quantum Fluids

Authors: Thierry Giamarchi

Categories: cond-mat.str-el cond-mat.quant-gas

Comments: Lectures notes of a course given at the "Les Houches Summer School of

Physics in Singapore" session on "Ultracold Gases and Quantum Information"

(29 June - 24 July, 2009); to be published by Oxford University Press

\\

In these notes I review the basic concepts of the effects of interactions on

quantum particles. I focuss here mostly on the case of fermions, but several

aspects of interacting bosons are mentioned as well. These notes have been

voluntarily kept at an elementary level and should be suitable for students

wanting to enter this field. I review the concept of Fermi liquid, and then

move to a description of the interaction effects, as well as the main models

that are used to tackle these questions. Finally I study the case of one

dimensional interacting particles that constitutes a fascinating special case.

\\ ( http://arxiv.org/abs/1007.1030 , 849kb)

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\\

arXiv:1007.1041

Date: Wed, 7 Jul 2010 03:32:42 GMT (996kb)

Title: Three attractively interacting fermions in a harmonic trap: Exact

solution, ferromagnetism, and high-temperature thermodynamics

Authors: Xia-Ji Liu, Hui Hu and Peter D. Drummond

Categories: cond-mat.quant-gas

Comments: 14 pages, 7 figures

\\

Three fermions with strongly repulsive interactions in a spherical harmonic

trap, constitute the simplest nontrivial system that can exhibit the onset of

itinerant ferromagnetism. Here, we present exact solutions for three trapped,

attractively interacting fermions near a Feshbach resonance. We analyze energy

levels on the upper branch of the resonance where the atomic interaction is

effectively repulsive. When the s-wave scattering length a is sufficiently

positive, three fully polarized fermions are energetically stable against a

single spin-flip, indicating the possibility of itinerant ferromagnetism, as

inferred in the recent experiment. We also investigate the high-temperature

thermodynamics of a strongly repulsive or attractive Fermi gas using a quantum

virial expansion. The second and third virial coefficients are calculated. The

resulting equations of state can be tested in future quantitative experimental

measurements at high temperatures and can provide a useful benchmark for

quantum Monte Carlo simulations.

\\ ( http://arxiv.org/abs/1007.1041 , 996kb)

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\\

arXiv:1007.1088

Date: Wed, 7 Jul 2010 09:35:49 GMT (121kb)

Title: Spin drag Hall effect in a rotating Bose mixture

Authors: H.J. van Driel, R.A. Duine, H.T.C. Stoof

Categories: cond-mat.quant-gas

Comments: 1 figure

\\

We show that in a rotating two-component Bose mixture, the spin drag between

the two different spin species shows a Hall effect. This spin drag Hall effect

can be observed experimentally by studying the out-of-phase dipole mode of the

mixture. We determine the damping of this mode due to spin drag as a function

of temperature. We find that due to Bose stimulation there is a strong

enhancement of the damping for temperatures close to the critical temperature

for Bose-Einstein condensation.

\\ ( http://arxiv.org/abs/1007.1088 , 121kb)

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\\

arXiv:1007.1130

Date: Wed, 7 Jul 2010 13:15:33 GMT (156kb)

Title: Metric Signature Transitions in Optical Metamaterials

Authors: Igor I. Smolyaninov, Evgenii E. Narimanov

Categories: physics.optics cond-mat.quant-gas gr-qc

Comments: 16 pages, 3 figures, accepted for publication in Physical Review

Letters

\\

We demonstrate that the extraordinary waves in indefinite metamaterials

experience (- - + +) effective metric signature. During a metric signature

change transition in such a metamaterial, a Minkowski space-time is "created"

together with large number of particles populating this space-time. Such

metamaterial models provide a table top realization of metric signature change

events suggested to occur in Bose-Einstein condensates and quantum gravity

theories.

\\ ( http://arxiv.org/abs/1007.1130 , 156kb)

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\\

arXiv:1007.1154 (*cross-listing*)

Date: Wed, 7 Jul 2010 14:48:37 GMT (70kb)

Title: Nonclassical lattice solitons in optical lattice via Electromagnetically

induced transparency

Authors: Yongyao Li, Zhonghui Yuan, Wei Pang and Yikun Liu

Categories: physics.optics quant-ph

\\

An optical four-level atomic discrete system through optical induction is

proposed. A theoretical scheme to produce nonclassical lattice solitons (NLS)

in the system is presented with the use of the effects of enhanced self-phase

modulation and the giant kerr effect in the electromagnetically induced

transparency. The power density and the photon flux can be tuned to a very low

level by the controlling field and the soliton can propagate with very slow

group velocity. By changing the sign of the detuning $\Delta_{1}$, both

in-phase and $\pi$ out-of-phase NLSs can be produced in this system.

\\ ( http://arxiv.org/abs/1007.1154 , 70kb)

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\\

arXiv:1007.1171

Date: Wed, 7 Jul 2010 15:59:53 GMT (173kb)

Title: Microcavity quantum-dot systems for non-equilibrium Bose-Einstein

condensation

Authors: I. M. Piper, P. R. Eastham, M. Ediger, A. M. Wilson, Y. Wu, M. Hugues,

M. Hopkinson and R. T. Phillips

Categories: cond-mat.mes-hall

Comments: 4 pages, 4 figures, to be published in J. Phys. Conf. Ser. for QD2010

\\

We review the practical conditions required to achieve a non-equilibrium BEC

driven by quantum dynamics in a system comprising a microcavity field mode and

a distribution of localised two-level systems driven to a step-like population

inversion profile. A candidate system based on eight 3.8nm layers of

In(0.23)Ga(0.77)As in GaAs shows promising characteristics with regard to the

total dipole strength which can be coupled to the field mode.

\\ ( http://arxiv.org/abs/1007.1171 , 173kb)

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\\

arXiv:1007.1172

Date: Wed, 7 Jul 2010 15:59:53 GMT (41kb)

Title: Entanglement from density measurements: analytical density-functional

for the entanglement of strongly correlated fermions

Authors: Vivian V. Fran\c{c}a and Irene D'Amico

Categories: quant-ph cond-mat.quant-gas cond-mat.str-el

Comments: 4 pages, 2 figures

\\

We derive an analytical density functional for the single-site entanglement

of the one-dimensional homogeneous Hubbard model, by means of an approximation

to the linear entropy. We show that this very simple density functional

reproduces quantitatively the exact results. We then use this functional as

input for a local-density approximation to the single-site entanglement of

inhomogeneous systems. We illustrate the power of this approach in a

harmonically confined system, which could simulate recent experiments with

ultracold atoms in optical lattices. The impressive quantitative agreement with

numerical calculations -- which includes reproducing subtle signatures of the

particle density stages -- shows that our density-functional can provide

entanglement calculations for actual experiments via density measurements.

\\ ( http://arxiv.org/abs/1007.1172 , 41kb)

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\\

arXiv:1007.1173

Date: Wed, 7 Jul 2010 16:04:22 GMT (350kb)

Title: Dynamics of Energy Transport in a Toda Ring

Authors: B. Sriram Shastry and A. P. Young

Categories: cond-mat.stat-mech

Comments: 34 pages, 11 figures

\\

We present results on the relationships between persistent currents and the

known conservation laws in the classical Toda ring. We also show that

perturbing the integrability leads to a decay of the currents at long times,

with a time scale that is determined by the perturbing parameter. We summarize

several known results concerning the Toda ring in 1-dimension, and present new

results relating to the frequency, average kinetic and potential energy, and

mean square displacement in the cnoidal waves, as functions of the wave vector

and a parameter that determines the non linearity.

\\ ( http://arxiv.org/abs/1007.1173 , 350kb)

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\\

arXiv:1007.1326

Date: Thu, 8 Jul 2010 10:02:42 GMT (134kb)

Title: Time-resolved measurement of Landau--Zener tunneling in different bases

Authors: G. Tayebirad, A. Zenesini, D. Ciampini, R. Mannella, O. Morsch, E.

Arimondo, N. L\"orch, and S. Wimberger

Categories: cond-mat.quant-gas

\\

A comprehensive study of the tunneling dynamics of a Bose--Einstein

condensate in a tilted periodic potential is presented. We report numerical and

experimental results on time-resolved measurements of the Landau--Zener

tunneling of ultracold atoms introduced by the tilt, which experimentally is

realized by accelerating the lattice. The use of different protocols enables us

to access the tunneling probability, numerically as well as experimentally, in

two different bases, namely, the adiabatic basis and the diabatic basis. The

adiabatic basis corresponds to the eigenstates of the lattice, and the diabatic

one to the free-particle momentum eigenstates. Our numerical and experimental

results are compared with existing two-state Landau--Zener models.

\\ ( http://arxiv.org/abs/1007.1326 , 134kb)

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\\

arXiv:1007.1342

Date: Thu, 8 Jul 2010 10:48:41 GMT (326kb)

Title: A Green's function decoupling scheme for the Edwards fermion-boson model

Authors: D M Edwards, S Ejima, A Alvermann, and H Fehske

Categories: cond-mat.str-el

Comments: 19 pages, 7 figures

\\

Holes in a Mott insulator are represented by spinless fermions in the

fermion-boson model introduced by Edwards. Although the physically interesting

regime is for low to moderate fermion density the model has interesting

properties over the whole density range. It has previously been studied at

half-filling in the one-dimensional (1D) case by numerical methods, in

particular exact diagonalization and density matrix renormalization group

(DMRG). In the present study the one-particle Green's function is calculated

analytically by means of a decoupling scheme for the equations of motion, valid

for arbitrary density in 1D, 2D and 3D with fairly large boson energy and zero

boson relaxation parameter. The Green's function is used to compute some ground

state properties, and the one-fermion spectral function, for fermion densities

n=0.1, 0.5 and 0.9 in the 1D case. The results are generally in good agreement

with numerical results obtained by DMRG and dynamical DMRG and new light is

shed on the nature of the ground state at different fillings. The Green's

function approximation is sufficiently successful in 1D to justify future

application to the 2D and 3D cases.

\\ ( http://arxiv.org/abs/1007.1342 , 326kb)

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\\

arXiv:1007.1377

Date: Thu, 8 Jul 2010 13:47:49 GMT (166kb)

Title: Coherence as ultrashort pulse train generator

Authors: Gevorg Muradyan and Mariam Hovhannisyan

Categories: quant-ph physics.optics

\\

Intense, well-controlled regular light pulse trains start to play a crucial

role in many fields of physics. We theoretically demonstrate a very simple and

robust technique for generating such periodic ultrashort pulses from a

continuous probe wave which propagates in a dispersive thermal gas media.

\\ ( http://arxiv.org/abs/1007.1377 , 166kb)

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\\

arXiv:1007.1402

Date: Thu, 8 Jul 2010 15:23:18 GMT (29kb)

Title: Effect of Quasiparticles Injection on the AC Response of a

Superconductor

Authors: G. Catelani, L. I. Glazman, K. E. Nagaev

Categories: cond-mat.supr-con

Comments: 9 pages, 1 figure

\\

We calculate the AC linear response of a superconductor in a nonequilibrium

electronic state. The nonequilibrium state is produced by injecting

quasiparticles into the superconductor from normal leads through asymmetric

tunnel contacts. The dissipative part of the response is drastically increased

by the injected quasiparticles and is proportional to their total number

regardless of the imbalance between the numbers of electron-like and hole-like

excitations.

\\ ( http://arxiv.org/abs/1007.1402 , 29kb)

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\\

arXiv:1007.1404 (*cross-listing*)

Date: Thu, 8 Jul 2010 15:29:22 GMT (1120kb)

Title: Multifractal wave functions of simple quantum maps

Authors: John Martin, Ignacio Garcia-Mata, Olivier Giraud and Bertrand Georgeot

Categories: nlin.CD cond-mat.mes-hall

Comments: 15 pages, 21 figures

\\

We study numerically multifractal properties of two models of one-dimensional

quantum maps, a map with pseudointegrable dynamics and intermediate spectral

statistics, and a map with an Anderson-like transition recently implemented

with cold atoms. Using extensive numerical simulations, we compute the

multifractal exponents of quantum wave functions and study their properties,

with the help of two different numerical methods used for classical

multifractal systems (box-counting method and wavelet method). We compare the

results of the two methods over a wide range of values. We show that the wave

functions of the Anderson map display a multifractal behavior similar to

eigenfunctions of the three-dimensional Anderson transition but of a weaker

type. Wave functions of the intermediate map share some common properties with

eigenfunctions at the Anderson transition (two sets of multifractal exponents,

with similar asymptotic behavior), but other properties are markedly different

(large linear regime for multifractal exponents even for strong

multifractality, different distributions of moments of wave functions, absence

of symmetry of the exponents). Our results thus indicate that the intermediate

map presents original properties, different from certain characteristics of the

Anderson transition derived from the nonlinear sigma model. We also discuss the

importance of finite-size effects.

\\ ( http://arxiv.org/abs/1007.1404 , 1120kb)

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\\

arXiv:1007.1416 (*cross-listing*)

Date: Thu, 8 Jul 2010 16:55:00 GMT (179kb)

Title: Two-center resonant photo ionization

Authors: B.Najjari, A.B.Voitkiv, C.M\"uller

Categories: physics.atom-ph quant-ph

Comments: 4 pages, 3 figures

\\

Photoionization of an atom $A$, in the presence of a neighboring atom $B$,

can proceed via resonant excitation of $B$ with subsequent energy transfer to

$A$ through two-center electron-electron correlation. We demonstrate that this

two-center mechanism can strongly outperform direct photoionization at

nanometer internuclear distances and possesses characteristic features in its

time development and the spectrum of emitted electrons.

\\ ( http://arxiv.org/abs/1007.1416 , 179kb)

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\\

arXiv:1007.1419 (*cross-listing*)

Date: Thu, 8 Jul 2010 17:07:02 GMT (168kb)

Title: Hyperfine structure of the ground state muonic $^3He$ atom

Authors: A. A. Krutov, A. P. Martynenko (Samara State U.)

Categories: hep-ph physics.atom-ph

Comments: 21 pages, 8 figures

Report-no: SSU-HEP-10/7

\\

On the basis of the perturbation theory in the fine structure constant

$\alpha$ and the ratio of the electron to muon masses we calculate one-loop

vacuum polarization and electron vertex corrections and the nuclear structure

corrections to the hyperfine splitting of the ground state of muonic helium

atom $(\mu\ e \ ^3_2He)$. We obtain total result for the ground state hyperfine

splitting $\Delta \nu^{hfs}=4166.471$ MHz which improves the previous

calculation of Lakdawala and Mohr due to the account of new corrections of

orders $\alpha^5$ and $\alpha^6$. The remaining difference between our

theoretical result and experimental value of the hyperfine splitting lies in

the range of theoretical and experimental errors and requires the subsequent

investigation of higher order corrections.

\\ ( http://arxiv.org/abs/1007.1419 , 168kb)

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\\

arXiv:1007.1435

Date: Thu, 8 Jul 2010 18:25:39 GMT (10kb)

Title: Unifying approach for fluctuation theorems from joint probability

distributions

Authors: Reinaldo Garcia-Garcia, Daniel Dominguez, Vivien Lecomte and Alejandro

B. Kolton

Categories: cond-mat.stat-mech

\\

Any decomposition of the total trajectory entropy production for Markovian

systems has a joint probability distribution satisfying a generalized detailed

fluctuation theorem, when all the contributing terms are odd with respect to

time reversal. The expression of the result does not bring into play dual

probability distributions, hence easing potential applications. We show that

several fluctuation theorems for perturbed non-equilibrium steady states are

unified and arise as particular cases of this general result. In particular, we

show that the joint probability distribution of the system and reservoir

trajectory entropies satisfy a detailed fluctuation theorem valid for all times

although each contribution does not do it separately.

\\ ( http://arxiv.org/abs/1007.1435 , 10kb)

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The replacements:

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\\

arXiv:1007.0059

replaced with revised version Sat, 3 Jul 2010 00:33:16 GMT (1371kb,D)

Title: Suppression of collisional shifts in a strongly interacting lattice

clock

Authors: Matthew D. Swallows, Michael Bishof, Yige Lin, Sebastian Blatt,

Michael J. Martin, Ana Maria Rey, and Jun Ye

Categories: quant-ph cond-mat.quant-gas physics.atom-ph

Comments: 11 pages, 5 figures

\\ ( http://arxiv.org/abs/1007.0059 , 1371kb)

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\\

arXiv:1003.6070

replaced with revised version Sun, 4 Jul 2010 12:06:57 GMT (186kb)

Title: Hardcore bosons on the dual of the bowtie lattice

Authors: Wanzhou Zhang, Laixi Li, and Wenan Guo

Categories: cond-mat.str-el cond-mat.quant-gas cond-mat.stat-mech

Comments: 10 figures

\\ ( http://arxiv.org/abs/1003.6070 , 186kb)

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\\

arXiv:1003.0424

replaced with revised version Mon, 5 Jul 2010 10:22:06 GMT (1128kb)

Title: Cold-Atom-Induced Control of an Optomechanical Device

Authors: M. Paternostro, G. De Chiara, and G. M. Palma

Categories: quant-ph cond-mat.quant-gas

Comments: 4 pages, 9 figures. Published version

Journal-ref: Phys. Rev. Lett. 104, 243602 (2010)

DOI: 10.1103/PhysRevLett.104.243602

\\ ( http://arxiv.org/abs/1003.0424 , 1128kb)

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\\

arXiv:1007.0100 (*cross-listing*)

replaced with revised version Mon, 5 Jul 2010 15:20:11 GMT (103kb)

Title: Decoherence effects in Bose-Einstein condensate interferometry. I

General Theory

Authors: B. J. Dalton

Categories: cond-mat.quant-gas quant-ph

Comments: Full version of paper, including all Appendices. Journal version only

includes Appendix A. Cross references to material in Appendices improved in

Version 2 (5 July 2010)

\\ ( http://arxiv.org/abs/1007.0100 , 103kb)

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\\

arXiv:1004.4231

replaced with revised version Tue, 6 Jul 2010 04:51:37 GMT (284kb)

Title: Spin-orbit coupling and perpendicular Zeeman field for fermionic cold

atoms: observation of the intrinsic anomalous Hall effect

Authors: Chuanwei Zhang

Categories: cond-mat.quant-gas cond-mat.mtrl-sci

Comments: 4 pages, 4 figures, minor modification of the laser setup

\\ ( http://arxiv.org/abs/1004.4231 , 284kb)

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\\

arXiv:1006.4426

replaced with revised version Tue, 6 Jul 2010 07:30:30 GMT (397kb)

Title: A nonlinear quantum piston for the controlled generation of vortex rings

Authors: Natalia G. Berloff, Victor M. Perez-Garcia

Categories: cond-mat.quant-gas nlin.PS

\\ ( http://arxiv.org/abs/1006.4426 , 397kb)

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\\

arXiv:1002.4446

replaced with revised version Tue, 6 Jul 2010 13:25:57 GMT (196kb)

Title: Quantum Quenches in an XXZ Spin Chain from a Spatially Inhomogeneous

Initial State

Authors: Jarrett Lancaster and Aditi Mitra

Categories: cond-mat.quant-gas

Comments: 17 pages, 9 figures. References added. Final published version

Journal-ref: Phys. Rev. E, 81, 061134 (2010)

\\ ( http://arxiv.org/abs/1002.4446 , 196kb)

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\\

arXiv:1003.4891

replaced with revised version Wed, 7 Jul 2010 14:19:38 GMT (54kb)

Title: Nuclear-spin-independent short-range three-body physics in ultracold

atoms

Authors: Noam Gross, Zav Shotan, Servaas Kokkelmans and Lev Khaykovich

Categories: cond-mat.quant-gas cond-mat.other

Comments: 4 pages, 2 figures

\\ ( http://arxiv.org/abs/1003.4891 , 54kb)

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\\

arXiv:1003.5808

replaced with revised version Wed, 7 Jul 2010 16:36:23 GMT (104kb)

Title: Breakdown of the superfluidity of a matter wave in a random environment

Authors: M. Albert, T. Paul, N. Pavloff and P. Leboeuf

Categories: cond-mat.quant-gas

Comments: 4 pages, 2 figures, final printed version

Journal-ref: Phys. Rev. A 82, 011602(R) (2010)

\\ ( http://arxiv.org/abs/1003.5808 , 104kb)

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\\

arXiv:1002.0265

replaced with revised version Wed, 7 Jul 2010 19:33:52 GMT (1050kb,D)

Title: Atom interferometry with trapped Bose-Einstein condensates: Impact of

atom-atom interactions

Authors: Julian Grond, Joerg Schmiedmayer, Ulrich Hohenester

Categories: cond-mat.quant-gas cond-mat.other

Comments: 28 pages, 13 figures, extended and corrected

Journal-ref: New J. Phys. 12, 065036 (2010)

DOI: 10.1088/1367-2630/12/6/065036

\\ ( http://arxiv.org/abs/1002.0265 , 1050kb)

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\\

arXiv:0911.0923

replaced with revised version Thu, 8 Jul 2010 13:24:22 GMT (1870kb)

Title: Stochastic Mean-Field Theory: Method and Application to the Disordered

Bose-Hubbard Model at Finite Temperature and Speckle Disorder

Authors: Ulf Bissbort, Ronny Thomale, Walter Hofstetter

Categories: cond-mat.dis-nn cond-mat.quant-gas

Comments: 19 pages, 15 figures. Extended definition of Bose glass phase, taking

collective excitations into account. 1 figure added, extended and updated

references

Journal-ref: Phys. Rev. A 81, 063643 (2010)

DOI: 10.1103/PhysRevA.81.063643

\\ ( http://arxiv.org/abs/0911.0923 , 1870kb)

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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 Wed Oct 20 2010 - 09:28:33 EST

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