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

Date: Thu, 03 Apr 2008 08:19:18 +1000

Date: Thu, 03 Apr 2008 08:19:18 +1000

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

Hi all,

There are a massive 42 preprints and 15 replacements this week. You guys

definitely work too hard...

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arXiv:0803.2081

Date: Fri, 14 Mar 2008 04:55:45 GMT (31kb)

Title: Defect production in non-linear quench across a quantum critical point

Authors: Diptiman Sen, K. Sengupta, and Shreyoshi Mondal

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

Comments: 4pg. 2 Figs., v1

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

We show that the defect density $n$, for a slow non-linear power-law quench

with a rate $\tau^{-1}$ and an exponent $\alpha>0$, which takes the system

through a critical point characterized by correlation length and dynamical

critical exponents $\nu$ and $z$, scales as $n \sim \tau^{-\alpha \nu d/

(\alpha z\nu+1)}$ [$n \sim (\alpha g^{(\alpha-1)/\alpha}/\tau)^{\nu

d/(z\nu+1)}$], if the quench takes the system across the critical point at time

$t=0$ [$t=t_0 \ne 0$], where $g$ is a non-universal constant and $d$ is the

system dimension. These scaling laws constitute the first theoretical results

for defect production in non-linear quenches across quantum critical points and

reproduce their well-known counterpart for linear quench ($\alpha=1$) as a

special case. We supplement our results with numerical studies of well-known

models and suggest experiments to test our theory.

\\ ( http://arxiv.org/abs/0803.2081 , 31kb)

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arXiv:0803.2084

Date: Fri, 14 Mar 2008 05:12:23 GMT (52kb)

Title: BCS-BEC crossover and effects of density fluctuations in a two-component

Fermi gas loaded on an optical lattice

Authors: H. Tamaki, Y. Ohashi, K. Miyake

Categories: cond-mat.mtrl-sci

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

We investigate the superfluid phase transition in a gas of Fermi atoms loaded

on a three-dimensional optical lattice. When the lattice potential is strong,

this system can be well described by an attractive Hubbard model. In this

model, we calculate the superfluid phase transition temperature Tc, including

both superfluid and (spin and charge) density fluctuations within the

self-consistent t-matrix theory and fluctuation exchange approximation,

respectively. Since we treat these fluctuations in a consistent manner, our

theory satisfies the required particle-hole symmetry over the entire BCS-BEC

crossover region. We show that charge density fluctuations compete against

superfluid fluctuations near the half-filling, leading to the suppression of

Tc. As a result, the maximum Tc is obtained away the half-filling. Since the

strong density fluctuations originate from the nesting property of the Fermi

surface at the half filling (which is absent in a uniform gas with no lattice

potential), our results would be useful in considering lattice effects on

strong-coupling superfluidity.

\\ ( http://arxiv.org/abs/0803.2084 , 52kb)

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arXiv:0803.2156

Date: Fri, 14 Mar 2008 13:25:13 GMT (323kb)

Title: Interaction induced trapping of a magnetically insensitive Bose-Einstein

Condensate

Authors: Stephan Middelkamp, Igor Lesanovsky, Peter Schmelcher

Categories: cond-mat.other

Comments: 10 pages, 4 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

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We demonstrate that atoms in magnetically insensitive hyperfine states (m=0)

can be trapped efficiently by a Bose-Einstein Condensate of the same atomic

species occupying a different hyperfine state. The latter is trapped

magnetically. Hyperfine state changing collisions, and therefore loss of the

trapped (m=0) atoms, are shown to be strongly inhibited in case of a low

density of the confined atomic cloud. We monitor the transition from a 'soft'

to a 'hard' effective potential by studying the backaction of the trapped (m=0)

atoms onto the condensate which provides their confinement. The controlled

release of the trapped atoms by shaping the condensate's wavefunction is

explored.

\\ ( http://arxiv.org/abs/0803.2156 , 323kb)

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arXiv:0803.2187

Date: Fri, 14 Mar 2008 15:45:08 GMT (148kb)

Title: Comment on "Splitting Times of Doubly Quantized Vortices in Dilute

Bose-Einstein Condensates"

Authors: K. Gawryluk, T. Karpiuk, M. Brewczyk, and K. Rzazewski

Categories: cond-mat.other

Comments: 1 page, 1 figure

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

In their recent Letter [1], Huhtamaki et al. theoretically investigated the

splitting of a topologically imprinted doubly charged vortex in to two singly

charged vortices as occurring in a dilute atomic Bose-Einstein conden sate.

They compare the results of simulation with recent experiment [2] and show that

the combination of gravitational sag and the time dependence of the trapping

potential alone are enough to explain the observed splitting times. In

particular, the numerically obtained dependence of the decay time on the peak

condensate density fits well the experimental data. Based on this agreement the

authors of Ref. [1] claim that, contrary to previous theoretical results [3],

the thermal excitations play no role in the experiment. We are going to show in

this Comment that there is no conflict between explanations in Ref. [1] and

[3]. In fact, a number of thermal (uncondensed) atoms appears in the system

while disturbing the gas. They continue to appear afterwords during the decay

of the vortex (i.e., when the separation between two cores of singly quantized

vortices is slowly increasing). The overall number of uncondensed atoms remains

approximately on the level of 20%, which is already at the edge of experimental

detection capabilities. However, the uncondensed atoms do not form the broad

cloud allowing the identification by fitting to a bimodal distribution - they

are rather located in the core of the vortex and therefore are harder to

detect.

[1] J.A.M. Huhtam\"aki et al., Phys. Rev. Lett. 97, 110406 (2006) [2] Y. Shin

et al., Phys. Rev. Lett. 93, 160406 (2004) [3] K. Gawryluk, M. Brewczyk, and K.

Rzazewski, J. Phys. B 39, L225 (2006)

\\ ( http://arxiv.org/abs/0803.2187 , 148kb)

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arXiv:0803.2206

Date: Fri, 14 Mar 2008 16:54:37 GMT (25kb)

Title: The Cooper pair from radio-frequency excitations in ultracold gases

Authors: J. Dukelsky and G. Ortiz

Categories: cond-mat.other

Comments: Three pages, 1 figure

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

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We discuss the concept of Cooper pair in the context of recent experimental

studies of radio-frequency excitations in ultracold atomic gases. We argue that

the threshold energy determines the size of the Cooper pair emergent from the

exact solution of the reduced BCS problem, and elaborate on the physical

distinction between bosonic and fermionic Cooper pairs.

\\ ( http://arxiv.org/abs/0803.2206 , 25kb)

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arXiv:0803.2097

Date: Fri, 14 Mar 2008 07:38:49 GMT (356kb,D)

Title: Delay of Squeezing and Entanglement using Electromagnetically Induced

Transparency in a Vapour Cell

Authors: G. H\'etet, B. C. Buchler, O. Gl\"ockl, M. T. L. Hsu, A. M. Akulshin,

H. -A. Bachor, and P. K. Lam

Categories: quant-ph

Comments: 8 pages, 5 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

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We demonstrate experimentally the delay of squeezed light and entanglement

using Electromagnetically Induced Transparency (EIT) in a rubidium vapour cell.

We perform quadrature amplitude measurements of the probe field and find no

appreciable excess noise from the EIT process. From an input squeezing of 3.1

dB at low sideband frequencies, we observed the survival of 2 dB of squeezing

at the EIT output. By splitting the squeezed light on a beam-splitter, we

generated biased entanglement between two beams. We transmit one of the

entangled beams through the EIT cell and correlate the quantum statistics of

this beam with its entangled counterpart. We experimentally observed a 2 $\mu$s

delay of the biased entanglement and obtained a preserved degree of

wavefunction inseparability of 0.71, below the unity value for separable

states.

\\ ( http://arxiv.org/abs/0803.2097 , 356kb)

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arXiv:0803.2151

Date: Fri, 14 Mar 2008 13:08:08 GMT (703kb)

Title: Two-dimensional array of microtraps with atomic shift register on a chip

Authors: S. Whitlock, R. Gerritsma, T. Fernholz, and R. J. C. Spreeuw

Categories: physics.atom-ph

Comments: 6 pages, 4 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

Arrays of trapped atoms are the ideal starting point for developing registers

comprising large numbers of physical qubits for processing quantum information.

One very promising approach involves neutral atom traps produced on

microfabricated devices known as atom chips, as almost arbitrary trap

configurations can be realised in a robust and compact package. Until now,

however, atom chip experiments have focused on small systems incorporating

single or only a few individual traps. In this letter we report experiments on

a vast two-dimensional array of trapped ultracold atom clouds prepared using a

simple magnetic-film atom chip. We are able to load atoms into hundreds of

tightly confining and optically resolved array sites. We then cool the

individual atom clouds in parallel to the critical temperature required for

quantum degeneracy. Finally, we shuttle atoms across the film surface utilising

the atom chip as an atomic shift register.

\\ ( http://arxiv.org/abs/0803.2151 , 703kb)

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arXiv:0803.2153

Date: Fri, 14 Mar 2008 14:14:48 GMT (48kb)

Title: Simulations of Sisyphus cooling including multiple excited states

Authors: F. Svensson, S. Jonsell, C. M. Dion

Categories: physics.atom-ph

Comments: 7 pages, 6 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

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We extend the theory for laser cooling in a near-resonant optical lattice to

include multiple excited hyperfine states. Simulations are performed treating

the external degrees of freedom of the atom, i.e., position and momentum,

classically, while the internal atomic states are treated quantum mechanically,

allowing for arbitrary superpositions. Whereas theoretical treatments including

only a single excited hyperfine state predict that the temperature should be a

function of lattice depth only, except close to resonance, experiments have

shown that the minimum temperature achieved depends also on the detuning from

resonance of the lattice light. Our results resolve this discrepancy.

\\ ( http://arxiv.org/abs/0803.2153 , 48kb)

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arXiv:0803.2265

Date: Mon, 17 Mar 2008 17:34:30 GMT (600kb)

Title: Phase Cat States with Bose-Einstein Condensates

Authors: F. Piazza, L. Pezze', and A. Smerzi

Categories: cond-mat.other

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

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We discuss the creation of quantum superposition states with distinct phases

(phase cat states) with a Bose-Einstein condensate trapped in a periodic

potential. The signature of the cat is con- tained in the phase distribution of

the interference patterns. Moreover, in the double well case, this distribution

shows a dramatic dependence on the parity of the total number of atoms. We

finally show that, for single well occupations up to a few hundred atoms, the

phase cats can be robust enough against decoherence to be experimentally

observable within current technology.

\\ ( http://arxiv.org/abs/0803.2265 , 600kb)

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arXiv:0803.2293

Date: Sat, 15 Mar 2008 12:48:21 GMT (23kb)

Title: Superfluid to insulator phase transition in a unitary Fermi gas

Authors: Nir Barnea

Categories: cond-mat.stat-mech

Comments: 4 pages,4 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

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We study the evolution of the energy gap in a unitary Fermi gas as a function

of temperature. To this end we approximate the Fermi gas by the Hubbard lattice

Hamiltonian and solve using the dynamical mean-field approximation. We have

found that below the critical temperature, Tc, the system is a superfluid and

the energy gap is decreasing monotonously. For temperatures above Tc the system

is an insulator and the corresponding energy gap is monotonously increasing.

\\ ( http://arxiv.org/abs/0803.2293 , 23kb)

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arXiv:0803.2312

Date: Sat, 15 Mar 2008 17:58:35 GMT (43kb)

Title: Effects of disorder on atomic density waves and spin-singlet dimers in

one-dimensional optical lattices

Authors: Gao Xianlong

Categories: cond-mat.str-el

Comments: 16 pages, submitted

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

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Using Bethe-ansatz density-functional theory, we study the one-dimensional

Hubbard model of confined attractively interacting fermions in the presence of

a uniformly distributed disorder. The strongly-correlated Luther-Emery nature

of the attractive one-dimensional Hubbard model is fully taken into account as

the reference system in the density-functional theory. The effects of the

disorder are investigated on atomic-density waves in the weak-to-intermediate

attractive interaction and on spin-singlet dimers of doubly occupied sites in

the strongly attractive regime. It is found that the atomic density waves are

sensitive to the disorder and the spin-singlet dimers of doubly occupied sites

are quite unstable against the disorder. We show also that very weak disorder

could smear the singularities in the stiffness, thus suppress the spin-singlet

pairs.

\\ ( http://arxiv.org/abs/0803.2312 , 43kb)

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arXiv:0803.2339

Date: Sun, 16 Mar 2008 08:07:24 GMT (158kb)

Title: Effects of Zero Mode and Thin Spectrum on the Life Time of Atomic Bose

Einstein Condensates

Authors: Turan Birol, \"Ozg\"ur E. M\"ustecapl{\i}o\u{g}lu

Categories: cond-mat.other

Comments: 8 pages, 9 figures, Proceeding of 14th Central European Workshop on

Quantum Optics To be published in European Physical Journal Special Topics

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

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Reviewing the ideas developed in, the ground state life time of a finite size

atomic Bose Einstein condensate is studied for coherent, squeezed coherent and

thermal coherent ground states. Ground state evolution of coherent and squeezed

coherent states in a double well potential is studied. Effects of thin spectrum

on Bose-Einstein condensates is discussed and quasiparticle excitation

lifetimes are calculated. It is shown that the effect of the states we use on

the free energy vanishes in the thermodynamic limit. Possible extension to a

double well potential and effect of a second broken symmetry is also discussed.

\\ ( http://arxiv.org/abs/0803.2339 , 158kb)

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arXiv:0803.2354

Date: Sun, 16 Mar 2008 15:08:30 GMT (866kb)

Title: Weakly non-ergodic Statistical Physics

Authors: Adi Rebenshtok, Eli Barkai

Categories: cond-mat.stat-mech

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

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We find a general formula for the distribution of time averaged observables

for weakly non-ergodic systems. Such type of ergodicity breaking is known to

describe certain systems which exhibit anomalous fluctuations, e.g. blinking

quantum dots and the sub-diffusive continuous time random walk model. When the

fluctuations become normal we recover usual ergodic statistical mechanics.

Examples of a particle undergoing fractional dynamics in a binding force field

are worked out in detail. We briefly discuss possible physical applications in

single particle experiments.

\\ ( http://arxiv.org/abs/0803.2354 , 866kb)

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arXiv:0803.2439

Date: Mon, 17 Mar 2008 17:53:00 GMT (122kb)

Title: Joule expansion of a pure many-body state

Authors: S. Camalet

Categories: cond-mat.other

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

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We derive the Joule expansion of an isolated perfect gas from the principles

of quantum mechanics. Contrary to most studies of irreversible processes which

consider composite systems, the gas many-body Hilbert space cannot be

factorised into Hilbert spaces corresponding to interesting and ignored degrees

of freedom. Moreover, the expansion of the gas into the entire accessible

volume is obtained for pure states. Still, the number particle density is

characterised by a chemical potential and a temperature. We discuss the special

case of a boson gas below the Bose condensation temperature.

\\ ( http://arxiv.org/abs/0803.2439 , 122kb)

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arXiv:0803.2442

Date: Mon, 17 Mar 2008 13:23:12 GMT (755kb)

Title: d-wave collapse and explosion of a dipolar Bose-Einstein condensate

Authors: Thierry Lahaye, Jonas Metz, Bernd Froehlich, Tobias Koch, Maximilian

Meister, Axel Griesmaier, Tilman Pfau, Hiroki Saito, Yuki Kawaguchi and

Masahito Ueda

Categories: cond-mat.other

Comments: 4 pages, 4 figures, submitted to Nature Physics

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

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We report on the observation of the d-wave symmetry in the collapse of a

dipolar quantum fluid. More specifically, we experimentally investigate the

collapse dynamics of a dipolar condensate of Cr atoms when the s-wave

scattering length is reduced below the critical value for which the condensate

becomes unstable. A complex dynamics, involving an anisotropic, d-wave

symmetric explosion of the condensate, is observed on time scales significantly

shorter than the trap period. At the same time, the condensate atom number

decreases abruptly during the collapse. We compare our experimental results

with numerical simulations of the three-dimensional Gross-Pitaevskii equation

including the contact and dipolar interactions as well as three-body losses. An

excellent agreement between experiment and theory is obtained. The numerical

simulation indicates that the collapse is accompanied by the formation of two

vortex rings with opposite circulations. The d-wave character of the dipolar

interaction, directly observed here in the collapse dynamics, is expected to

enrich considerably the physics of quantum gases.

\\ ( http://arxiv.org/abs/0803.2442 , 755kb)

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arXiv:0803.2488

Date: Mon, 17 Mar 2008 17:18:48 GMT (56kb)

Title: BCS-BEC Crossover of a Quasi-two-dimensional Fermi Gas: the Significance

of Dressed Molecules

Authors: Wei Zhang, G.-D. Lin, and L.-M. Duan

Categories: cond-mat.str-el cond-mat.supr-con

Comments: 5 pages, 3 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

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We study the crossover of a quasi-two-dimensional Fermi gas trapped in the

radial plane from the Bardeen-Cooper-Schrieffer (BCS) regime to the

Bose-Einstein condensation (BEC) regime by crossing a wide Feshbach resonance.

Using an effective two-dimensional Hamiltonian with renormalized interaction

between atoms and dressed molecules, we calculate the zero temperature cloud

size and number density distribution and conclude that the results are

consistent with the picture of a BCS-BEC crossover. These results are in clear

contrast to the predictions of an effective two-dimensional Hamiltonian with

renormalized atom-atom interaction, where a constant cloud size and identical

density profile are expected for arbitrary detunings. This inconsistence

indicates that the inclusion of dressed molecules is essential to describe

quasi-two-dimensional Fermi systems, especially on the BEC side of the Feshbach

resonance.

\\ ( http://arxiv.org/abs/0803.2488 , 56kb)

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arXiv:0803.2493

Date: Mon, 17 Mar 2008 17:48:12 GMT (69kb)

Title: Vortex dynamics in rotating counterflow and plane Couette and Poiseuille

turbulence in superfluid Helium

Authors: David Jou, Michele Sciacca and Maria Stella Mongiovi'

Categories: cond-mat.other

Comments: 18 pages, 2 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

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An equation previously proposed to describe the evolution of vortex line

density in rotating counterflow turbulent tangles in superfluid helium is

generalized to incorporate nonvanishing barycentric velocity and velocity

gradients. Our generalization is compared with an analogous approach proposed

by Lipniacki, and with experimental results by Swanson et al. in rotating

counterflow, and it is used to evaluate the vortex density in plane Couette and

Poiseuille flows of superfluid helium.

\\ ( http://arxiv.org/abs/0803.2493 , 69kb)

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arXiv:0803.1914

Date: Thu, 13 Mar 2008 08:09:07 GMT (608kb)

Title: Geometric phases and quantum phase transitions

Authors: Shi-Liang Zhu

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

Comments: Invited review article for IJMPB; material covered till June 2007; 10

pages

Journal-ref: International Journal of Modern Physics B 22, 561-581 (2008)

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

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Quantum phase transition is one of the main interests in the field of

condensed matter physics, while geometric phase is a fundamental concept and

has attracted considerable interest in the field of quantum mechanics. However,

no relevant relation was recognized before recent work. In this paper, we

present a review of the connection recently established between these two

interesting fields: investigations in the geometric phase of the many-body

systems have revealed so-called "criticality of geometric phase", in which

geometric phase associated with the many-body ground state exhibits

universality, or scaling behavior in the vicinity of the critical point. In

addition, we address the recent advances on the connection of some other

geometric quantities and quantum phase transitions. The closed relation

recently recognized between quantum phase transitions and some of geometric

quantities may open attractive avenues and fruitful dialog between different

scientific communities.

\\ ( http://arxiv.org/abs/0803.1914 , 608kb)

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arXiv:0803.2425

Date: Mon, 17 Mar 2008 11:48:40 GMT (403kb,D)

Title: Space-like Separation in a Bell Test assuming Gravitationally Induced

Collapses

Authors: D. Salart, A. Baas, J.A.W. van Houwelingen, N. Gisin, and H. Zbinden

Categories: quant-ph

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

We report on a Bell experiment with space-like separation assuming that the

measurement time is related to gravity-induced state reduction. Two energy-time

entangled photons are sent through optical fibers and directed into unbalanced

interferometers at two receiving stations separated by 18 km. At each station,

the detection of a photon triggers the displacement of a macroscopic mass. The

timing ensures space-like separation from the moment a photon enters its

interferometer until the mass has moved. 2-photon interference fringes with a

visibility of up to 90.5% are obtained, leading to a violation of Bell

inequality.

\\ ( http://arxiv.org/abs/0803.2425 , 403kb)

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arXiv:0803.2446

Date: Mon, 17 Mar 2008 13:52:33 GMT (928kb,D)

Title: Low-energy excitations of a boson pair in a double-well trap

Authors: D.S. Murphy and J.F. McCann

Categories: quant-ph

Comments: 16 pages, 15 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

The states of a boson pair in a one-dimensional double-well potential are

investigated. Properties of the ground and lowest excited states of this system

are studied, including the two-particle wavefunction, momentum pair

distribution and entanglement. The effects of varying both the barrier height

and the effective interaction strength are investigated.

\\ ( http://arxiv.org/abs/0803.2446 , 928kb)

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arXiv:0803.2517

Date: Mon, 17 Mar 2008 20:41:19 GMT (547kb)

Title: Radio frequency spectroscopy of a strongly imbalanced Feshbach-resonant

Fermi gas

Authors: Martin Veillette, Eun Gook Moon, Austen Lamacraft, Leo Radzihovsky,

Subir Sachdev, and D.E. Sheehy

Categories: cond-mat.str-el cond-mat.supr-con

Comments: 10 pages, 5 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

A sufficiently large species imbalance (polarization) in a two-component

Feshbach resonant Fermi gas is known to drive the system into its normal state.

We show that the resulting strongly-interacting state is a conventional Fermi

liquid, that is, however, strongly renormalized by pairing fluctuations. Using

a controlled 1/N expansion, we calculate the properties of this state with a

particular emphasis on the atomic spectral function, the momentum distribution

functions displaying the Migdal discontinuity, and the radio frequency (RF)

spectrum. We discuss the latter in the light of the recent experiments of

Schunck et al. (cond-mat/0702066) on such a resonant Fermi gas, and show that

the observations are consistent with a conventional, but strongly renormalized

Fermi-liquid picture.

\\ ( http://arxiv.org/abs/0803.2517 , 547kb)

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arXiv:0803.2535

Date: Tue, 18 Mar 2008 02:18:28 GMT (908kb)

Title: Formation of Quantum Shock Waves by Merging and Splitting Bose-Einstein

Condensates

Authors: J.J. Chang, P. Engels, M. A. Hoefer

Categories: cond-mat.other

Comments: 10 pages, 8 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

The processes of merging and splitting dilute-gas Bose-Einstein condensates

are studied in the nonadiabatic, high-density regime. Rich dynamics are found.

Depending on the experimental parameters, uniform soliton trains containing

more than ten solitons or the formation of a high-density bulge as well as

quantum (or dispersive) shock waves are observed experimentally within merged

BECs. Our numerical simulations indicate the formation of many vortex rings. In

the case of splitting a BEC, the transition from sound-wave formation to

dispersive shock-wave formation is studied by use of increasingly stronger

splitting barriers. These experiments realize prototypical dispersive shock

situations.

\\ ( http://arxiv.org/abs/0803.2535 , 908kb)

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arXiv:0803.2574

Date: Tue, 18 Mar 2008 07:43:55 GMT (422kb)

Title: Kelvin Waves in Bose-Einstein Condensates

Authors: T. P. Simula, T. Mizushima, and K. Machida

Categories: cond-mat.other

Comments: 4 pages, 4 figure

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

We have theoretically investigated Kelvin waves of quantized vortex lines in

trapped Bose-Einstein condensates. Counter-rotating perturbation induces an

elliptical instability to the initially straight vortex line, driven by a

parametric resonance between a quadrupole surfon and a pair of kelvons of

opposite momenta. Subsequently Kelvin waves rapidly decay to longer wavelengths

emitting sound waves in the process. We present a modified Kelvin wave

dispersion relation for trapped superfluids and propose a simple method to

excite Kelvin waves of specific wave number.

\\ ( http://arxiv.org/abs/0803.2574 , 422kb)

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arXiv:0803.2579

Date: Tue, 18 Mar 2008 09:29:12 GMT (311kb)

Title: Magnetization profile and core level spectroscopy in a multiply

quantized vortex of imbalanced Fermi superfluids

Authors: K. M. Suzuki, T. Mizushima, M. Ichioka, K. Machida

Categories: cond-mat.supr-con

Comments: 10 pages, 6 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

The core structure of multiply quantized vortices is theoretically

investigated in fermionic superfluid near Feshbach resonance. Under population

imbalance in two hyperfine spin states, the vortex core is filled in by the

``paramagnetic moment''. Here, we find the spatial oscillation of the

magnetization inside the core sensitively due to the topological structure of

the pairing field, in the range from the weak coupling regime to the unitary

limit. This magnetization inside the giant core reveals the winding number of

the vortex and directly results from the low-lying quasiparticle states bound

inside the core. It is therefore proposed that the density profile experiment

using phase contrast imaging can provide the spectroscopy of novel core level

structures in giant vortices. To help the understanding on these outcomes, we

also derive the analytic solution for the low-lying quasiparticle states inside

the core of a multiply quantized vortex.

\\ ( http://arxiv.org/abs/0803.2579 , 311kb)

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arXiv:0803.2666

Date: Tue, 18 Mar 2008 15:58:59 GMT (488kb)

Title: Theory of cavity-assisted microwave cooling of polar molecules

Authors: Margareta Wallquist, Peter Rabl, Mikhail D. Lukin and Peter Zoller

Categories: quant-ph

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

We analyze cavity-assisted cooling schemes for polar molecules in the

microwave domain, where molecules are excited on a rotational transition and

energy is dissipated via strong interactions with a lossy stripline cavity, as

recently proposed by A. Andre et al., Nature Physics 2, 636 (2006). We identify

the dominant cooling and heating mechanisms in this setup and study cooling

rates and final temperatures in various parameter regimes. In particular we

analyze the effects of a finite environment temperature on the cooling

efficiency, and find minimal temperature and optimized cooling rate in the

strong drive regime. Further we discuss the trade-off between efficiency of

cavity cooling and robustness with respect to ubiquitous imperfections in a

realistic experimental setup, such as anharmonicity of the trapping potential.

\\ ( http://arxiv.org/abs/0803.2666 , 488kb)

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arXiv:0803.2708

Date: Tue, 18 Mar 2008 20:04:11 GMT (614kb)

Title: Meta-nematic, smectic and crystalline phases of dipolar fermions in an

optical lattice

Authors: J. Quintanilla, S. T. Carr, J. J. Betouras

Categories: cond-mat.other cond-mat.str-el

Comments: 10 pages, 5 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

Strongly correlated quantum matter (from high-temperature superconductors,

through oxides and heavy fermions to quantum Hall devices) remains an

outstanding scientific challenge. In it, electron itineracy survives in spite

of strong interactions. A general framework was proposed for its understanding

in [Kivelson, Fradkin and Emery, Nature 393, 550-553 (1998)]. It rests on

liquid crystalline phases intervening between the Fermi gas and the Wigner

crystal or Mott insulator as the strength of correlations increases. In this

work we propose an alternative realisation of the relevant physics in an

ultra-cold atomic gas. It exploits optical lattices and dipolar interactions to

realise a particularly simple model which can be tuned systematically. We

analyze theoretically the system and discover that three phase transitions

compete: a meta-nematic, quasi-1D to 2D transition, where inter-chain

interaction leads to the closing of the Fermi surface; a transition into a

striped phase; and crystallisation of the fermions into a `checkerboard'

pattern.

\\ ( http://arxiv.org/abs/0803.2708 , 614kb)

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\\

arXiv:0803.2763

Date: Wed, 19 Mar 2008 08:46:39 GMT (77kb)

Title: Double species condensate with tunable interspecies interactions

Authors: G. Thalhammer, G. Barontini, L. De Sarlo, J. Catani, F. Minardi, M.

Inguscio

Categories: cond-mat.other

Comments: 4 pages, 4 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

We produce Bose-Einstein condensates of two different species, $^{87}$Rb and

$^{41}$K, in an optical dipole trap in proximity of interspecies Feshbach

resonances. We discover and characterize two Feshbach resonances, located

around 35 and 79 G, by observing the three-body losses and the elastic

cross-section. The narrower resonance is exploited to create a double species

condensate with tunable interactions. Our system opens the way to the

exploration of double species Mott insulators and, more in general, of the

quantum phase diagram of the two species Bose-Hubbard model.

\\ ( http://arxiv.org/abs/0803.2763 , 77kb)

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\\

arXiv:0803.2815

Date: Wed, 19 Mar 2008 14:58:31 GMT (84kb)

Title: Magnetic field-induced one-magnon Raman scattering in the magnon

Bose-Einstein condensation phase of TlCuCl$_{3}$

Authors: Haruhiko Kuroe, Kouhei Kusakabe, Akira Oosawa, Tomoyuki Sekine, Fumiko

Yamada, Hidekazu Tanaka, and Masashige Matsumoto

Categories: cond-mat.str-el

Comments: 6 pages, 4 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

We report the observation of the $A_{\rm g}$-symmetric one-magnon Raman peak

in the magnon Bose-Einstein condensation phase of TlCuCl$_{3}$. Its Raman shift

traces the one-magnon energy at the magnetic $\Gamma$ point, and its intensity

is proportional to the squared transverse magnetization. The appearance of the

one-magnon Raman scattering originates from the exchange magnon Raman process

and reflects the change of the magnetic-state symmetry. Using the bond-operator

representation, we theoretically clarify the Raman selection rules, being

consistent with the experimental results.

\\ ( http://arxiv.org/abs/0803.2815 , 84kb)

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\\

arXiv:0803.2851

Date: Wed, 19 Mar 2008 17:27:34 GMT (937kb)

Title: Rise and fall of hidden string order of lattice bosons

Authors: Erez Berg, Emanuele G. Dalla Torre, Thierry Giamarchi and Ehud Altman

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

Comments: 15 pages, 8 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

We investigate the ground state properties of a newly discovered phase of one

dimensional lattice bosons with extended interactions (see E. G. Dalla Torre et

al., Phys. Rev. Lett. \textbf{97}, 260401 (2006)). The new phase, termed the

Haldane Insulator (HI) in analogy with the gapped phase of spin-1 chains, is

characterized by a non local order parameter, which can only be written as an

infinite string in terms of the bosonic densities. We show that the string

order can nevertheless be probed with physical fields that couple locally, via

the effect those fields have on the quantum phase transitions separating the

exotic phase from the conventional Mott and density wave phases. Using a field

theoretical analysis we show that a perturbation which breaks lattice inversion

symmetry gaps the critical point separating the Mott and Haldane phases and

eliminates the sharp distinction between them. This is remarkable given that

neither of these phases involves broken inversion symmetry. We also investigate

the evolution of the phase diagram with the tunable coupling between parallel

chains in an optical lattice setup. We find that inter-chain tunneling destroys

the direct phase transition between the Mott and Haldane insulators by

establishing an intermediate superfluid phase. On the other hand coupling the

chains only by weak repulsive interactions does not modify the structure of the

phase diagram. The theoretical predictions are confirmed with numerical

calculations using the Density Matrix Renormalization Group (DMRG).

\\ ( http://arxiv.org/abs/0803.2851 , 937kb)

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\\

arXiv:0803.2857

Date: Wed, 19 Mar 2008 18:01:36 GMT (388kb)

Title: Magnetic phases of one-dimensional lattices with 2 to 4 fermions per

site

Authors: J.-P. Nikkarila, M. Koskinen, S.M. Reimann and M. Manninen

Categories: cond-mat.str-el cond-mat.mes-hall

Comments: 8 pages, 6 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

We study the spectral and magnetic properties of one-dimensional lattices

filled with 2 to 4 fermions (with spin 1/2) per lattice site. We use a

generalized Hubbard model that takes account all interactions on a lattice

site, and solve the many-particle problem by exact diagonalization. We find an

intriguing magnetic phase diagram which includes ferromagnetism, spin-one

Heisenberg antiferromagnetism, and orbital antiferromagnetism.

\\ ( http://arxiv.org/abs/0803.2857 , 388kb)

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\\

arXiv:0803.2861

Date: Wed, 19 Mar 2008 18:25:19 GMT (308kb,D)

Title: Shell-Model Monte Carlo Simulations of Pairing in Few-Fermion Systems

Authors: N. T. Zinner, K. M{\o}lmer, C. \"Ozen, K. Langanke, D. J. Dean

Categories: cond-mat.supr-con cond-mat.other

Comments: Revtex format, 4+ pages, 3 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

We study a trapped system of fermions with a zero-range two-body interaction

on the BCS side of unitarity using the Shell-Model Monte Carlo method. The

method provides ab initio results in the low N limit where the BCS mean-field

theory is not applicable. The energy and pairing properties are presented as

functions of interaction strength, particle number, and temperature. In the

interesting region where the typical matrix elements of the two-body

interaction is comparable to the level spacing of the trap we find large

odd-even effects and signatures of shell structure. As a function of

temperature, we observe the disappearance of these effects as in a phase

transition.

\\ ( http://arxiv.org/abs/0803.2861 , 308kb)

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\\

arXiv:0803.2686

Date: Tue, 18 Mar 2008 19:45:05 GMT (18kb)

Title: Simulation of Many-Body Hamiltonians using Perturbation Theory with

Bounded-Strength Interactions

Authors: Sergey Bravyi, David P. DiVincenzo, Daniel Loss and Barbara M. Terhal

Categories: quant-ph cond-mat.other math-ph math.MP

Comments: v1: 8 pages Latex, 1 figure

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

We show how to map a given n-qubit target Hamiltonian with bounded-strength

k-body interactions onto a simulator Hamiltonian with two-body interactions,

such that the ground-state energy of the target and the simulator Hamiltonians

are the same up to an extensive error O(epsilon n) for arbitrary small epsilon.

The strength of interactions in the simulator Hamiltonian depends on epsilon

and k but does not depend on n. We accomplish this reduction using a new way of

deriving an effective low-energy Hamiltonian which relies on the

Schrieffer-Wolff transformation of many-body physics.

\\ ( http://arxiv.org/abs/0803.2686 , 18kb)

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\\

arXiv:0803.2712

Date: Wed, 19 Mar 2008 09:51:39 GMT (691kb)

Title: Nonlinear spectroscopy of photons bound to one atom

Authors: I. Schuster, A. Kubanek, A. Fuhrmanek, T. Puppe, P.W.H. Pinkse, K.

Murr and G. Rempe

Categories: quant-ph

Comments: 7 figures, Nature Physics

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

Optical nonlinearities typically require macroscopic media, thereby making

their implementation at the quantum level an outstanding challenge. Here we

demonstrate a nonlinearity for one atom enclosed by two highly reflecting

mirrors. We send laser light through the input mirror and record the light from

the output mirror of the cavity. For weak laser intensity, we find the

vacuum-Rabi resonances. But for higher intensities, we find an additional

resonance. It originates from the fact that the cavity can accommodate only an

integer number of photons and that this photon number determines the

characteristic frequencies of the coupled atom-cavity system. We selectively

excite such a frequency by depositing at once two photons into the system and

find a transmission which increases with the laser intensity squared. The

nonlinearity differs from classical saturation nonlinearities and is direct

spectroscopic proof of the quantum nature of the atom-cavity system. It

provides a photon-photon interaction by means of one atom, and constitutes a

step towards a two-photon gateway or a single-photon transistor.

\\ ( http://arxiv.org/abs/0803.2712 , 691kb)

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\\

arXiv:0803.2725

Date: Tue, 18 Mar 2008 21:54:39 GMT (160kb)

Title: Arbitrary Coherent Superpositions of Quantized Vortices in Bose-Einstein

Condensates from Orbital Angular Momentum Beams of Light

Authors: Sulakshana Thanvanthri, Kishore T. Kapale and Jonathan P. Dowling

Categories: quant-ph

Comments: 13 pages, 11 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

We recently proposed a scheme for the creation of coherent superpositions of

vortex states in Bose-Einstein condensates (BEC) using orbital angular momentum

(OAM) states of light [Phys. Rev. Lett. 95, 173601 (2005)]. Here we discuss

further technical details of the proposal, provide alternative,

time-reversal-symmetric scheme for transfer of a superposition of OAM states of

light to the BEC via a procedure analogous to the traditional STimulated Raman

Adiabatic Passage (STIRAP) technique, and discuss an alternative trap

configuration conducive for sustaining large charge vortices. Superpositions of

OAM states of light, created using experimental techniques, can be transfered

to an initially nonrotating BEC via a specially devised Raman coupling scheme.

The techniques proposed here open up avenues to study coherent interaction of

OAM states of light with matter. The study could also be employed for

performing various quantum information processing tasks with OAM states of

light--including a memory for a quantum state of the initial superposition.

\\ ( http://arxiv.org/abs/0803.2725 , 160kb)

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\\

arXiv:0803.2733

Date: Tue, 18 Mar 2008 23:08:29 GMT (745kb)

Title: Real-time control of the periodicity of a standing wave: an optical

accordion

Authors: T. C. Li, H. Kelkar, D. Medellin, and M. G. Raizen

Categories: quant-ph

Comments: 6 pages, 6 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

We report an experimental method to create optical lattices with real-time

control of their periodicity. We demonstrate a continuous change of the lattice

periodicity from 0.96 $\mu$m to 11.2 $\mu$m in one second, while the center

fringe only moves less than 2.7 $\mu$m during the whole process. This provides

a powerful tool for controlling ultracold atoms in optical lattices, where

small spacing is essential for quantum tunneling, and large spacing enables

single-site manipulation and spatially resolved detection.

\\ ( http://arxiv.org/abs/0803.2733 , 745kb)

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\\

arXiv:0803.2788

Date: Wed, 19 Mar 2008 11:18:27 GMT (507kb)

Title: Simultaneous cooling and entanglement of mechanical modes of a

micromirror in an optical cavity

Authors: Claudiu Genes, David Vitali and Paolo Tombesi

Categories: quant-ph

Comments: submitted to NJP

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

Laser cooling of a mechanical mode of a resonator by the radiation pressure

of a detuned optical cavity mode has been recently demonstrated by various

groups in different experimental configurations. Here we consider the effect of

a second mechanical mode with a close, but different resonance frequency. We

show that the nearby mechanical resonance is simultaneously cooled by the

cavity field, provided that the difference between the two mechanical

frequencies is not too small. When this frequency difference becomes smaller

than the effective mechanical damping of the secondary mode, the two cooling

processes interfere destructively and cavity cooling is suppressed in the limit

of identical mechanical frequencies. We show that also the entanglement

properties of the steady state of the tripartite system crucially depend upon

on the difference between the two mechanical frequencies. If the latter is

larger than the effective damping of the second mechanical mode, the state

shows fully tripartite entanglement and each mechanical mode is entangled with

the cavity mode. If instead the frequency difference is smaller, the steady

state is a two-mode biseparable state, inseparable only when one splits the

cavity mode from the two mechanical modes. In this latter case, the

entanglement of each mechanical mode with the cavity mode is extremely fragile

with respect to temperature.

\\ ( http://arxiv.org/abs/0803.2788 , 507kb)

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\\

arXiv:0803.2828

Date: Wed, 19 Mar 2008 16:02:13 GMT (914kb)

Title: Quantum optics with bosons and fermions

Authors: Alain Aspect (LCFIO), Denis Boiron (LCFIO), Christoph Westbrook

(LCFIO)

Categories: quant-ph

Comments: English version of "Optique atomique quantique : apr\`es les bosons,

les fermions"

Proxy: ccsd hal-00265624

Journal-ref: Europhysics News 39, 1 (2008) 25

DOI: 10.1051/epn2008004

\\

Atom optics, a field which takes much inspiration from traditional optics,

has advanced to the point that some of the fundamental experiments of quantum

optics, involving photon correlations, have found atomic analogs. We discuss

some recent experiments on atom bunching and anti-bunching as well as some

prospects for extending them to the field of many body physics.

\\ ( http://arxiv.org/abs/0803.2828 , 914kb)

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\\

arXiv:0803.2900

Date: Wed, 19 Mar 2008 21:45:58 GMT (38kb)

Title: Canonical Trajectories and Critical Coupling of the Bose-Hubbard

Hamiltonian in a Harmonic Trap

Authors: G.G. Batrouni, H. R. Krishnamurthy, K. W. Mahmud, V.G. Rousseau, R.T.

Scalettar

Categories: cond-mat.other cond-mat.stat-mech

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

Quantum Monte Carlo (QMC) simulations and the Local Density Approximation

(LDA) are used to map the constant particle number (canonical) trajectories of

the Bose Hubbard Hamiltonian confined in a harmonic trap onto the $(\mu/U,t/U)$

phase diagram of the uniform system. Generically, these curves do not intercept

the tips of the Mott insulator (MI) lobes of the uniform system. This

observation necessitates a clarification of the appropriate comparison between

critical couplings obtained in experiments on trapped systems with those

obtained in QMC simulations. The density profiles and visibility are also

obtained along these trajectories. Density profiles from QMC in the confined

case are compared with LDA results.

\\ ( http://arxiv.org/abs/0803.2900 , 38kb)

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\\

arXiv:0803.2922

Date: Thu, 20 Mar 2008 03:17:19 GMT (699kb)

Title: Theory of correlations between ultra-cold bosons released from an

optical lattice

Authors: E. Toth, A. M. Rey and P. B. Blakie

Categories: cond-mat.other

Comments: 18 pages, 11 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

In this paper we develop a theoretical description of the correlations

between ultra-cold bosons after free expansion from confinement in an optical

lattice. We consider the system evolution during expansion and give criteria

for a far field regime. We develop expressions for first and second order

two-point correlations based on a variety of commonly used approximations to

the many-body state of the system including Bogoliubov, meanfield decoupling,

and particle-hole perturbative solution about the perfect Mott-insulator state.

Using these approaches we examine the effects of quantum depletion and pairing

on the system correlations. Comparison with the directly calculated correlation

functions is used to justify a Gaussian form of our theory from which we

develop a general three-dimensional formalism for inhomogeneous lattice

systems.

\\ ( http://arxiv.org/abs/0803.2922 , 699kb)

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\\

arXiv:0803.2947

Date: Thu, 20 Mar 2008 09:23:51 GMT (399kb,D)

Title: Spreading of correlations and entanglement after a quench in the

Bose-Hubbard model

Authors: Andreas Laeuchli, Corinna Kollath

Categories: cond-mat.other

Comments: 19 pages, 9 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

We investigate the spreading of information in a Bose-Hubbard system after a

sudden parameter change. In particular, we study the time-evolution of

correlations and entanglement following a quench. The investigated quantities

show a light-cone like evolution, i.e. the spreading with a finite velocity. We

discuss the relation of this veloctiy to other characteristic velocities of the

system, like the sound velocity. The entanglement is investigated using two

different measures, the von-Neuman entropy and mutual information. Whereas the

von-Neumann entropy grows rapidly with time the mutual information can as well

decrease after an initial increase. Additionally we show that the static von

Neuman entropy characterises the location of the quantum phase transition.

\\ ( http://arxiv.org/abs/0803.2947 , 399kb)

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\\

arXiv:0803.2997

Date: Thu, 20 Mar 2008 13:47:49 GMT (125kb)

Title: Mode-locking and mode-competition in a non-equilibrium solid-state

condensate

Authors: P. R. Eastham

Categories: cond-mat.other cond-mat.str-el

Comments: 5 pages, 2 figures

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

A trapped polariton condensate with continuous pumping and decay is analyzed

using a generalized Gross-Pitaevskii model. Whereas an equilibrium condensate

is characterized by a macroscopic occupation of a ground state, here the

steady-states take more general forms. Some are characterized by a large

population in an excited state, and others by large populations in several

states. In the latter case, the highly-populated states synchronize to a common

frequency above a critical density. Estimates for the critical density of this

synchronization transition are consistent with experiments.

\\ ( http://arxiv.org/abs/0803.2997 , 125kb)

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\\

arXiv:0803.3039

Date: Thu, 20 Mar 2008 17:45:56 GMT (27kb)

Title: The Nonlinear Dirac Equation in Bose-Einstein Condensates: Foundation

and Symmetries

Authors: L. H. Haddad and L. D. Carr

Categories: cond-mat.other

Comments: 11 pages, 1 figure

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\

We show that Bose-Einstein condensates in a honeycomb optical lattice are

described by a nonlinear Dirac equation in the long wavelength, mean field

limit. Unlike nonlinear Dirac equations posited by particle theorists, which

are designed to preserve the principle of relativity, i.e., Poincar\'e

covariance, the nonlinear Dirac equation for Bose-Einstein condensates breaks

this symmetry. We present a rigorous derivation of the nonlinear Dirac equation

from first principles. We provide a thorough discussion of all symmetries

broken and maintained.

\\ ( http://arxiv.org/abs/0803.3039 , 27kb)

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The replacements:

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\\

arXiv:0801.3307

replaced with revised version Fri, 14 Mar 2008 05:03:01 GMT (188kb)

Title: Solitons in two-dimensional Bose-Einstein condensates

Authors: Shunji Tsuchiya, Franco Dalfovo, Lev P. Pitaevskii

Categories: cond-mat.supr-con cond-mat.other

Comments: 4 pages, 4 figures, revised version

\\ ( http://arxiv.org/abs/0801.3307 , 188kb)

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\\

arXiv:cond-mat/0606029

replaced with revised version Sat, 15 Mar 2008 09:35:47 GMT (71kb)

Title: Finite Size Effect on Bose-Einstein Condensation

Authors: Shyamal Biswas

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

Comments: Ph.D. Thesis

\\ ( http://arxiv.org/abs/cond-mat/0606029 , 71kb)

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\\

arXiv:0711.2141

replaced with revised version Mon, 17 Mar 2008 10:52:12 GMT (43kb)

Title: Macroscopic Periodic Tunneling of Fermi Atoms in the BCS-BEC Crossover

Authors: L. Salasnich, N. Manini and F. Toigo

Categories: cond-mat.stat-mech cond-mat.soft cond-mat.supr-con

Comments: 6 pages 3 figures revtex

\\ ( http://arxiv.org/abs/0711.2141 , 43kb)

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\\

arXiv:0712.2443

replaced with revised version Sat, 15 Mar 2008 16:53:47 GMT (59kb)

Title: The model of interacting spatial permutations and its relation to the

Bose gas

Authors: Daniel Ueltschi

Categories: cond-mat.stat-mech math-ph math.MP

Comments: 14 pages

\\ ( http://arxiv.org/abs/0712.2443 , 59kb)

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\\

arXiv:0802.3972 (*cross-listing*)

replaced with revised version Mon, 17 Mar 2008 13:59:14 GMT (196kb)

Title: Exotic quantum phase transitions in a Bose-Einstein condensate coupled

to an optical cavity

Authors: Gang Chen, Xiaoguang Wang, J.-Q. Liang, and Z. D. Wang

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

Comments: 4 pages; figures 1 and 3 are modified; topos are corrected

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\ ( http://arxiv.org/abs/0802.3972 , 196kb)

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\\

arXiv:0802.1688

replaced with revised version Mon, 17 Mar 2008 14:01:08 GMT (280kb)

Title: Observation of Ultra-narrow Electromagnetically Induced Transparency and

Slow Light using Purely Electronic Spins in a Hot Atomic Vapor

Authors: F. Goldfarb, J. Ghosh, M. David, J. Ruggiero, T. Chaneli\`ere, J.-L.

Le Gou\"et, H. Gilles, R. Ghosh, and F. Bretenaker

Categories: quant-ph

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

\\ ( http://arxiv.org/abs/0802.1688 , 280kb)

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\\

arXiv:0710.5099

replaced with revised version Tue, 18 Mar 2008 10:42:58 GMT (391kb)

Title: Creation of resilient entangled states and a resource for

measurement-based quantum computation with optical superlattices

Authors: B. Vaucher, A. Nunnenkamp, and D. Jaksch

Categories: cond-mat.other quant-ph

Comments: 23 pages, 6 figures, IOP style, published in New Journal of Physics.

Minor corrections/few typos removed

Journal-ref: New J. Phys. 10, 023005 (2008)

DOI: 10.1088/1367-2630/10/2/023005

\\ ( http://arxiv.org/abs/0710.5099 , 391kb)

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\\

arXiv:0711.3627

replaced with revised version Mon, 17 Mar 2008 21:35:42 GMT (59kb)

Title: Collective Excitations of Trapped Imbalanced Fermion Gases

Authors: Achilleas Lazarides and Bert Van Schaeybroeck

Categories: cond-mat.other cond-mat.stat-mech

Comments: 4 pages; accepted for publication in PRA

\\ ( http://arxiv.org/abs/0711.3627 , 59kb)

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\\

arXiv:0802.1882

replaced with revised version Tue, 18 Mar 2008 14:59:30 GMT (27kb)

Title: Quasiparticles, coherence and nonlinearity: exact simulations of

RF-spectroscopy of strongly interacting one-dimensional Fermi gases

Authors: M. J. Leskinen, V. Apaja, J. Kajala, P. Torma

Categories: cond-mat.supr-con cond-mat.other

Comments: 4 pages, 3 figures

\\ ( http://arxiv.org/abs/0802.1882 , 27kb)

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\\

arXiv:quant-ph/0703160

replaced with revised version Tue, 18 Mar 2008 16:43:25 GMT (14kb)

Title: Quantum origin of quantum jumps: Breaking of unitary symmetry induced by

information transfer and the transition from quantum to classical

Authors: Wojciech Hubert Zurek

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

Comments: For comments see Seth Lloyd, NATURE 450, 1167 (2007)

Journal-ref: Phys. Rev. A 76, 052110 (2007)

\\ ( http://arxiv.org/abs/quant-ph/0703160 , 14kb)

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\\

arXiv:0710.0208

replaced with revised version Wed, 19 Mar 2008 14:21:19 GMT (256kb)

Title: Hanbury Brown and Twiss correlations in atoms scattered from colliding

condensates

Authors: Klaus Molmer, A. Perrin, V. Krachmalnicoff, V. Leung, D. Boiron, A.

Aspect, C. I. Westbrook

Categories: cond-mat.other quant-ph

Comments: Minor corrections. reference updated

Journal-ref: Phys. Rev. A 77, 033601 (2008);

\\ ( http://arxiv.org/abs/0710.0208 , 256kb)

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\\

arXiv:0801.4771

replaced with revised version Wed, 19 Mar 2008 09:13:34 GMT (112kb,D)

Title: Self-organization of a Bose-Einstein condensate in an optical cavity

Authors: D. Nagy, G. Szirmai, P. Domokos

Categories: quant-ph cond-mat.other

Comments: 11 pages, final version. Accepted for publication in EPJD

\\ ( http://arxiv.org/abs/0801.4771 , 112kb)

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\\

arXiv:0708.2845

replaced with revised version Thu, 20 Mar 2008 10:31:28 GMT (217kb)

Title: Transport of a quantum degenerate heteronuclear Bose-Fermi mixture in a

harmonic trap

Authors: C. Klempt, T. Henninger, O. Topic, J. Will, St. Falke, W. Ertmer, and

J. Arlt

Categories: cond-mat.other

Comments: 7 pages, 8 figures

\\ ( http://arxiv.org/abs/0708.2845 , 217kb)

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\\

arXiv:0709.2653

replaced with revised version Wed, 19 Mar 2008 20:32:00 GMT (467kb)

Title: Quantum Fluctuations in the Superfluid State of the BCS-BEC Crossover

Authors: Roberto B. Diener, Rajdeep Sensarma, Mohit Randeria

Categories: cond-mat.other cond-mat.supr-con

Comments: 23 pages, 11 figures

Journal-ref: Physical Review A 77, 023626 (2008)

DOI: 10.1103/PhysRevA.77.023626

\\ ( http://arxiv.org/abs/0709.2653 , 467kb)

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\\

arXiv:0801.3060

replaced with revised version Thu, 20 Mar 2008 18:52:28 GMT (93kb)

Title: Spin density-functional theory for imbalanced interacting Fermi gases in

highly elongated harmonic traps

Authors: Gao Xianlong and Reza Asgari

Categories: cond-mat.str-el

Comments: Minor corrections, three references added, Phys. Rev. A 77, 033604

(2008)

\\ ( http://arxiv.org/abs/0801.3060 , 93kb)

------------------------------------------------------------------------------

Till next time,

Matt.

-- ========================================================================= Dr M. J. Davis, Senior Lecturer in Physics School of Physical Sciences, email: mdavis_at_physics.uq.edu.au University of Queensland, ph : +61 7 334 69824 Brisbane, QLD 4072, fax : +61 7 336 51242 Australia. http://www.physics.uq.edu.au/people/mdavis/ ========================================================================= Matt's arXiv selection: weekly summary of cold-atom papers from arXiv.org http://www.physics.uq.edu.au/people/mdavis/matts_arXiv/ ========================================================================= Legal stuff: Unless stated otherwise, this e-mail represents only the views of the sender and not the views of the University of Queensland =========================================================================Received on Thu Apr 03 2008 - 09:47:57 EST

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