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

Date: Mon, 22 May 2006 18:04:39 +1000 (EST)

Date: Mon, 22 May 2006 18:04:39 +1000 (EST)

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

Hi all,

I've had a busy day today, and so the arXiv selection email was delayed until

now. However, you have the bonus that it includes the latest arXiv mailings as

posted a couple of hours ago.

Home page at: http://www.physics.uq.edu.au/people/mdavis/matts_arXiv/

On with the abstracts:

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

\\

Paper: quant-ph/0605098

Date: Thu, 11 May 2006 02:39:28 GMT (253kb)

Title: Deterministic single photons via conditional quantum evolution

Authors: D. N. Matsukevich, T. Chaneliere, S. D. Jenkins, S.-Y. Lan, T. A. B.

Kennedy, and A. Kuzmich

Comments: 5 pages, 3 figures

\\

A source of deterministic single photons is proposed and demonstrated by the

application of a measurement-based feedback protocol to a heralded single

photon source consisting of an ensemble of cold rubidium atoms. Our source is

stationary and produces a photoelectric detection record with sub-Poissonian

statistics.

\\ ( http://arXiv.org/abs/quant-ph/0605098 , 253kb)

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

\\

Paper: cond-mat/0605315

Date: Thu, 11 May 2006 20:57:40 GMT (73kb)

Title: Dipolar Bose-Einstein condensates with dipole-dependent scattering

length

Authors: Shai Ronen, Daniele C. E. Bortolotti, D. Blume, and John L. Bohn

Subj-class: Statistical Mechanics

\\

We consider a Bose-Einstein condensate of polar molecules in a harmonic trap,

where the effective dipole may be tuned by an external field. We demonstrate

that taking into account the dependence of the scattering length on the dipole

moment is essential to reproducing the correct energies and for predicting the

stability of the condensate. We do this by comparing Gross-Pitaevskii

calculations with diffusion Monte Carlo calculations. We find very good

agreement between the results obtained by these two approaches once the dipole

dependence of the scattering length is taken into account. We also examine the

behavior of the condensate in non-isotropic traps.

\\ ( http://arXiv.org/abs/cond-mat/0605315 , 73kb)

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

\\

Paper: cond-mat/0605335

Date: Fri, 12 May 2006 15:01:59 GMT (214kb)

Title: Ultracold polarized Fermi gas at intermediate temperatures

Authors: Jani-Petri Martikainen

Comments: 6 pages, 5 figures

Subj-class: Statistical Mechanics

\\

We consider the polarized two-component Fermi gas at non-zero temperatures.

We point out that stable polarized paired states which are more stable than

their phase separated counterparts with unpolarized superfluid region can exist

below the critical temperature. We also solve the system behavior in a trap

using the local density approximation and find gradually increasing

polarization in the center of the system as the temperature is increased.

However, in the strongly interacting region the central polarization increases

most rapidly close to the mean-field critical temperature, which is known to be

substantially higher than the critical temperature for superfluidity. This

indicates that most of the phase separation occurs in the fluctuation region

prior to superfluidity and that the polarization in the actual superfluid is

modest.

\\ ( http://arXiv.org/abs/cond-mat/0605335 , 214kb)

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

\\

Paper: cond-mat/0605343

Date: Fri, 12 May 2006 14:33:27 GMT (93kb)

Title: Composite fermion theory of rapidly rotating two-dimensional bosons

Authors: N. Regnault, C.C. Chang, Th. Jolicoeur, J.K. Jain

Comments: 12 pages, 9 figures. Conference proceeding. BEC 2005 Italy

Subj-class: Mesoscopic Systems and Quantum Hall Effect

Journal-ref: J. Phys. B: At. Mol. Opt. Phys. 39 (2006) S89-S99

DOI: 10.1088/0953-4075/39/10/S09

\\

Ultracold neutral bosons in a rapidly rotating atomic trap have been

predicted to exhibit fractional quantum Hall-like states. We describe how the

composite fermion theory, used in the description of the fractional quantum

Hall effect for electrons, can be applied to interacting bosons. Numerical

evidence supporting the formation of composite fermions, each being the bound

state of a boson and one flux quantum, is shown for filling fractions of the

type nu=p/(p+1), both by spectral analysis and by direct comparison with trial

wave functions. The rapidly rotating system of two-dimensional bosons thus

constitutes an interesting example of "statistical transmutation," with bosons

behaving like composite fermions. We also describe the difference between the

electronic and the bosonic cases when p approaches infinity. Residual

interactions between composite fermions are attractive in this limit, resulting

in a paired composite-fermion state described by the Moore-Read wave function.

\\ ( http://arXiv.org/abs/cond-mat/0605343 , 93kb)

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

\\

Paper: cond-mat/0506046

replaced with revised version Fri, 12 May 2006 00:09:49 GMT (174kb)

Title: Equation of state of a superfluid Fermi gas in the BCS-BEC crossover

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

Comments: 7 pages, 4 figures, published version in Europhysics Letters, a long

preprint with details will appear soon

Subj-class: Superconductivity; Statistical Mechanics

Journal-ref: Europhys. Lett. 74, 574 (2006)

DOI: 10.1209/epl/i2006-10023-y

\\ ( http://arXiv.org/abs/cond-mat/0506046 , 174kb)

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

\\

Paper: cond-mat/0602483

replaced with revised version Fri, 12 May 2006 03:37:34 GMT (84kb)

Title: Ground state properties of one-dimensional ultracold Bose gases in a

hard-wall trap

Authors: Yajiang Hao, Yunbo Zhang, J.-Q. Liang and Shu Chen

Comments: 7 pages, 6 figures, typos corrected, version to be published in Phys.

Rev. A

Subj-class: Strongly Correlated Electrons

\\ ( http://arXiv.org/abs/cond-mat/0602483 , 84kb)

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

\\

Paper: quant-ph/0601137

replaced with revised version Fri, 12 May 2006 07:03:32 GMT (465kb)

Title: Theoretical study of a cold atom beam splitter

Authors: Naceur Gaaloul (PPM, LSAMA), Annick Suzor-Weiner (PPM), Laurence

Pruvost (LAC), Mourad Telmini (LSAMA), Eric Charron (PPM)

Proxy: ccsd ccsd-00017414

\\ ( http://arXiv.org/abs/quant-ph/0601137 , 465kb)

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

\\

Paper: cond-mat/0605350

Date: Fri, 12 May 2006 20:41:41 GMT (223kb)

Title: The Fermi-Hubbard model at unitarity

Authors: Evgeni Burovski, Nikolay Prokof'ev, Boris Svistunov and Matthias

Troyer

Comments: 27 pages, iopart class file. Submitted to New J. Phys

Subj-class: Superconductivity; Statistical Mechanics

\\

We simulate the dilute attractive Fermi-Hubbard model in the unitarity regime

using a diagrammatic determinant Monte Carlo algorithm with worm-type updates.

We obtain the dependence of the critical temperature on the filling factor

$\nu$ and, by extrapolating to $\nu \to 0$, determine the universal critical

temperature of the continuum unitary Fermi gas in units of Fermi energy:

$T_c/\epsilon_F=0.152(7)$. We also determine the thermodynamic functions and

show how the Monte Carlo results can be used for accurate thermometry of a

trapped unitary gas.

\\ ( http://arXiv.org/abs/cond-mat/0605350 , 223kb)

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

\\\

Paper: cond-mat/0605351

Date: Mon, 15 May 2006 16:19:48 GMT (740kb)

Title: Spontaneous symmetry breaking in a quenched ferromagnetic spinor Bose

condensate

Authors: L. E. Sadler, J. M. Higbie, S. R. Leslie, M. Vengalattore and D. M.

Stamper-Kurn

Comments: 6 pages, 4 figures

Subj-class: Statistical Mechanics

\\

A central goal in condensed matter and modern atomic physics is the

exploration of many-body quantum phases and the universal characteristics of

quantum phase transitions in so far as they differ from those established for

thermal phase transitions. Compared with condensed-matter systems, atomic gases

are more precisely constructed and also provide the unique opportunity to

explore quantum dynamics far from equilibrium. Here we identify a second-order

quantum phase transition in a gaseous spinor Bose-Einstein condensate, a

quantum fluid in which superfluidity and magnetism, both associated with

symmetry breaking, are simultaneously realized. $^{87}$Rb spinor condensates

were rapidly quenched across this transition to a ferromagnetic state and

probed using in-situ magnetization imaging to observe spontaneous symmetry

breaking through the formation of spin textures, ferromagnetic domains and

domain walls. The observation of topological defects produced by this symmetry

breaking, identified as polar-core spin-vortices containing non-zero spin

current but no net mass current, represents the first phase-sensitive in-situ

detection of vortices in a gaseous superfluid.

\\ ( http://arXiv.org/abs/cond-mat/0605351 , 740kb)

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

\\

Paper: cond-mat/0605369

Date: Mon, 15 May 2006 07:38:51 GMT (477kb)

Title: Anisotropic Kosterlitz-Thouless Transition Induced by Hard-Wall

Boundaries

Authors: Gary A. Williams

Comments: 4 pages, 3 figures, submitted to PRB

Subj-class: Statistical Mechanics

\\

The spatial dependence of the superfluid density is calculated for the

Kosterlitz-Thouless transition in the presence of hard-wall boundaries, for the

case of a single wall bounding the half-infinite plane, and for a superfluid

strip bounded by two walls. The boundaries induce additional vortices that

cause the superfluid density to become anisotropic, with the tensor component

perpendicular to the wall falling to zero at the wall, whereas the component

parallel to the wall remains finite. The effects of the boundaries are found to

extend over all measured length scales, since the correlation length is

infinite in the superfluid phase.

\\ ( http://arXiv.org/abs/cond-mat/0605369 , 477kb)

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

\\

Paper: cond-mat/0605374

Date: Mon, 15 May 2006 09:49:58 GMT (600kb)

Title: Statics and dynamics of BEC's in double square well potentials

Authors: E. Infeld, P. Zi\'{n}, J. Goca{\l}ek and M. Trippenbach

Comments: 11 pages, 6 figures

Subj-class: Other

\\

In this paper we treat the behavior of Bose Einstein condensates in double

square well potentials, both of equal and different depths. For even depth,

symmetry preserving solutions to the relevant nonlinear Schr\"{o}dinger

equation is known, just as in the linear limit. When the nonlinearity is strong

enough, symmetry breaking solutions also exist, side by side with the symmetric

one. Interestingly, solutions almost entirely localized in one of the wells are

known as an extreme case. Here we outline a method for obtaining all these

solutions for repulsive interactions. The bifurcation point at which, for

critical nonlinearity, the asymmetric solutions branch off from the symmetry

preserving ones is found analytically. We also find this bifurcation point and

treat the solutions generally via a Josephson Junction model.

When the confining potential is in the form of two wells of different depth,

interesting new phenomena appear. This is true of both the occurrence of the

bifurcation point for the static solutions, and also of the dynamics of phase

and amplitude varying solutions. Again a generalization of the Josephson model

proves useful. The stability of solutions is treated briefly.

\\ ( http://arXiv.org/abs/cond-mat/0605374 , 600kb)

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

\\

Paper: cond-mat/0605388

Date: Mon, 15 May 2006 14:54:34 GMT (140kb)

Title: Transition from Free to Interacting Composite Fermions away from

$\nu$=1/3

Authors: Y. Gallais, T.H. Kirschenmann, I. Dujovne, C.F. Hirjibehedin, A.

Pinczuk, B.S. Dennis, L.N. Pfeiffer and K.W. West

Comments: 4 pages, 5 figures

Subj-class: Mesoscopic Systems and Quantum Hall Effect; Strongly Correlated

Electrons

\\

Spin excitations from a partially populated composite fermion level are

studied above and below $\nu=1/3$. In the range $2/7<\nu<2/5$ the experiments

uncover significant departures from the non-interacting composite fermion

picture that demonstrate the increasing impact of interactions as quasiparticle

Landau levels are filled. The observed onset of a transition from free to

interacting composite fermions could be linked to condensation into the higher

order states suggested by transport experiments and numerical evaluations

performed in the same filling factor range.

\\ ( http://arXiv.org/abs/cond-mat/0605388 , 140kb)

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

\\

Paper: quant-ph/0605114

Date: Sat, 13 May 2006 01:00:03 GMT (277kb)

Title: Reaching 7Li BEC with a Mini-Trap

Authors: Ruquan Wang, Mingchang Liu, Francesco Minardi and Mark Kasevich

Comments: 7 pages, 10 figures

\\

A novel mm-scale Ioffe-Pritchard trap is used to achieve Bose-Einstein

condensation in 7Li. The trap employs free-standing copper coils integrated

onto a direct-bond copper surface electrode structure. The trap achieves a

radial magnetic gradient of 420 G/cm, an axial oscillation frequency of 50 Hz

and a trap depth of 66 G with a 100 A drive current and 7 W total power

dissipation.

\\ ( http://arXiv.org/abs/quant-ph/0605114 , 277kb)

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

\\

Paper: quant-ph/0605122

Date: Mon, 15 May 2006 06:00:09 GMT (114kb)

Title: Efficient retrieval of a single excitation stored in an atomic ensemble

Authors: Julien Laurat, Hugues de Riedmatten, Daniel Felinto, Chin-wen Chou,

Erik Schomburg, H. Jeff Kimble

\\

We report significant improvements in the retrieval efficiency of a single

excitation stored in an atomic ensemble and in the subsequent generation of

strongly correlated pairs of photons. A 50% probability to transform the stored

excitation into one photon in a well-defined spatio-temporal mode at the output

of the ensemble is demonstrated. These improvements are illustrated by the

generation of high-quality heralded single photons with a suppression of the

two-photon component below 1% of the value for a coherent state. A broad

characterization of our system is performed for different parameters in order

to provide input for the future design of realistic quantum networks.

\\ ( http://arXiv.org/abs/quant-ph/0605122 , 114kb)

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

\\

Paper: quant-ph/0605123

Date: Mon, 15 May 2006 07:18:19 GMT (8kb)

Title: Exact Solutions of a Non-Polynomially Nonlinear Schrodinger Equation

Authors: R. Parwani and H. S. Tan

Comments: 11 pages

\\

A nonlinear generalisation of Schrodinger's equation had previously been

obtained using information-theoretic arguments. The nonlinearities in that

equation were of a nonpolynomial form, equivalent to the occurence of

higher-derivative nonlinear terms at all orders. Here we construct some exact

solutions to that equation in 1+1 dimensions. On the half-line, the solutions

resemble exponentially damped Bloch waves even though no external periodic

potential is included: the periodicity is induced by the nonpolynomiality. The

solutions are nonperturbative as they do not reduce to solutions of the linear

theory in the limit that the nonlinearity parameter vanishes. An intriguing

feature of the solutions is their infinite degeneracy: for a given energy,

there exists a very large arbitrariness in the normalisable wavefunctions. We

also consider solutions to a q-deformed version of the nonlinear equation and

discuss a natural discretisation implied by the nonpolynomiality. Finally, we

contrast the properties of our solutions with other solutions of nonlinear

Schrodinger equations in the literature and suggest some possible applications

of our results in the domains of low-energy and high-energy physics.

\\ ( http://arXiv.org/abs/quant-ph/0605123 , 8kb)

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

\\

Paper: quant-ph/0605125

Date: Mon, 15 May 2006 13:45:45 GMT (266kb)

Title: Splitting times of doubly quantized vortices in dilute Bose-Einstein

condensates

Authors: J. A. M. Huhtam\"aki (1), M. M\"ott\"onen (2), T. Isoshima (3), V.

Pietil\"a (1), and S. M. M. Virtanen (1) ((1) Laboratory of Physics, Helsinki

University of Technology, Finland, (2) Low Temperature Laboratory, Helsinki

University of Technology, Finland, (3) Institute of Physics, Academia Sinica,

Taiwan)

Comments: 5 pages, 5 figures

\\

Recently, the splitting of a topologically created doubly quantized vortex

into two singly quantized vortices was experimentally investigated in dilute

atomic cigar-shaped Bose-Einstein condensates [Y. Shin et al., Phys. Rev. Lett.

93, 160406 (2004)]. In particular, the dependency of the splitting time on the

peak particle density was studied. We present results of theoretical

simulations which closely mimic the experimental set-up. Contrary to previous

theoretical studies, claiming that thermal excitations are the essential

mechanism in initiating the splitting, we show that the combination of

gravitational sag and time dependency of the trapping potential alone suffices

to split the doubly quantized vortex in time scales which are in good agreement

with the experiments. We also study the dynamics of the resulting singly

quantized vortices which typically intertwine--especially, a peculiar vortex

chain structure appears for certain parameter values.

\\ ( http://arXiv.org/abs/quant-ph/0605125 , 266kb)

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

\\

Paper: quant-ph/0605129

Date: Mon, 15 May 2006 15:27:16 GMT (388kb)

Title: Phase Space Quantum Mechanics - Direct

Authors: S. Nasiri, Y. Sobouti, and F. Taati

Comments: 16 pages

\\

Conventional approach to quantum mechanics in phase space, (q,p), is to take

the operator based quantum mechanics of Schrodinger, or and equivalent, and

assign a c-number function in phase space to it. We propose to begin with a

higher level of abstraction, in which the independence and the symmetric role

of q and p is maintained throughout, and at once arrive at phase space state

functions. Upon reduction to the q- or p-space the proposed formalism gives the

conventional quantum mechanics, however, with a definite rule for ordering of

factors of non commuting observables. Further conceptual and practical merits

of the formalism are demonstrated throughout the text.

\\ ( http://arXiv.org/abs/quant-ph/0605129 , 388kb)

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

\\

Paper: physics/0605111

Date: Fri, 12 May 2006 21:50:34 GMT (220kb)

Title: Antiblockade in Rydberg excitation of an ultracold lattice gas

Authors: Cenap Ates, Thomas Pohl, Thomas Pattard, Jan M. Rost

Comments: 4 pages, 6 figures

Subj-class: Atomic Physics

\\

It is shown that the two-step excitation scheme typically used to create an

ultracold Rydberg gas can be described with an effective two-level rate

equation, greatly reducing the complexity of the optical Bloch equations. This

allows us to solve the many-body problem of interacting cold atoms with a Monte

Carlo technique. Our results reproduce the Rydberg blockade effect. However, we

demonstrate that an Autler-Townes double peak structure in the two-step

excitation scheme, which occurs for moderate pulse lengths as used in the

experiment, can give rise to an antiblockade effect. It is observable in a

lattice gas with regularly spaced atoms. Since the antiblockade effect is

robust against a large number of lattice defects it should be experimentally

realizable with an optical lattice created by CO$_{2}$ lasers.

\\ ( http://arXiv.org/abs/physics/0605111 , 220kb)

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

\\

Paper: cond-mat/0605393

Date: Tue, 16 May 2006 02:50:19 GMT (113kb)

Title: Bose-Einstein condensates in RF-dressed adiabatic potentials

Authors: M. White, H. Gao, M. Pasienski, B. DeMarco

Subj-class: Other

\\

Bose-Einstein condensates of $^{87}$Rb atoms are transferred into

radio-frequency (RF) induced adiabatic potentials and the properties of the

corresponding dressed states are explored. We demonstrate that measurements of

the Zeeman populations of dressed condensates are a sensitive probe of RF

magnetic field strength. We also show that adiabatic potentials can be used to

trap atom gases in novel geometries, including suspending a cigar-shaped cloud

above a curved sheet of atoms.

\\ ( http://arXiv.org/abs/cond-mat/0605393 , 113kb)

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

\\

Paper: cond-mat/0605402

Date: Tue, 16 May 2006 09:21:33 GMT (257kb)

Title: Bosonization of Interacting Fermions in Arbitrary Dimensions

Authors: Peter Kopietz (Frankfurt)

Comments: 287 pages, 33 figues. This review has been published in the lecture

note series by Springer Verlag, but it is currently out of print. It will be

available again via Springer Verlag in the future, see

http://www.springerlink.com/openurl.asp?genre=journal&issn=1616-6361 and

http://www.springerlink.com/openurl.asp?genre=journal&issn=0940-7677

Permission by Springer Verlag to publish this review in this archive has been

obtained

Subj-class: Strongly Correlated Electrons; Statistical Mechanics

Journal-ref: Peter Kopietz, Bosonization of interacting fermions in arbitrary

dimensions, (Springer, Berlin, 1997)

\\

This review is a summary of my work (partially in collaboration with Kurt

Schoenhammer) on higher-dimensional bosonization during the years 1994-1996. It

has been published as a book entitled `` Bosonization of interacting fermions

in arbitrary dimensions" by Springer Verlag (Lecture Notes in Physics m48,

Springer, Berlin, 1997). I have NOTrevised this review, so that there is no

reference to the literature after 1996. However, the basic ideas underlying the

functional bosonization approach outlined in this review are still valid today.

\\ ( http://arXiv.org/abs/cond-mat/0605402 , 257kb)

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

\\

Paper: cond-mat/0605405

Date: Tue, 16 May 2006 10:10:12 GMT (201kb)

Title: Issues on the transport of one dimensional systems

Authors: X. Zotos

Comments: Conference on "Statistical Physics of Quantum Systems - novel orders

and dynamics -" Sendai, July 2004

Subj-class: Strongly Correlated Electrons; Statistical Mechanics

Journal-ref: Journal of Physical Society of Japan, Suppl. v.74, p.173 (2005)

\\

In this paper, we will critically discuss recent theoretical and experimental

developments on the transport of one dimensional quantum systems. In

particular, we will focus on open issues and controversial results related to

the finite temperature dynamics of integrable quantum models. These singular

systems are commonly used in the description of quasi-one dimensional

materials. They have recently attracted a lot of interest in connection to the

interpretation of experiments, specially after the discovery of unusual thermal

conductivity in magnetic compounds.

\\ ( http://arXiv.org/abs/cond-mat/0605405 , 201kb)

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

\\

Paper: cond-mat/0605407

Date: Tue, 16 May 2006 10:18:11 GMT (91kb)

Title: Dimensional Effects on Solitonic Matter and Optical Waves with Normal

and Anomalous Dispersion

Authors: L. Salasnich, A. Parola and L. Reatto

Comments: To be published in Journal of Physics B: At. Mol. Opt. Phys

Subj-class: Other; Statistical Mechanics

\\

We investigate bright and dark solitons with anomalous or normal dispersion

and under transverse harmonic confinement. In matter waves, positive atomic

mass implies anomalous dispersion (kinetic spreading) while negative mass gives

normal dispersion (kinetic shrinking). We find that, contrary to the strictly

one-dimensional case, the axial and transverse profiles of these solitons

crucially depend on the strength of the nonlinearity and on their dispersive

properties. In particular, we show that, like bright solitons with anomalous

dispersion, also dark solitons with normal dispersion disappear at a critical

axial density. Our predictions are useful for the study of atomic matter waves

in Bose-Einstein condensates and also for optical bullets in inhomogeneous Kerr

media.

\\ ( http://arXiv.org/abs/cond-mat/0605407 , 91kb)

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

\\

Paper: cond-mat/0605409

Date: Tue, 16 May 2006 11:53:41 GMT (69kb)

Title: Bogoliubov modes of a dipolar condensate in a cylindrical trap

Authors: Shai Ronen, Daniele E. C. Bortolotti, and John L. Bohn

Subj-class: Statistical Mechanics

\\

The calculation of properties of Bose-Einstein condensates with dipolar

interactions has proven a computationally intensive problem due to the long

range nature of the interactions, limiting the scope of applications. In

particular, the lowest lying Bogoliubov excitations in three dimensional

harmonic trap with cylindrical symmetry were so far computed in an indirect

way, by Fourier analysis of time dependent perturbations, or by approximate

variational methods. We have developed a very fast and accurate numerical

algorithm based on the Hankel transform for calculating properties of dipolar

Bose-Einstein condensates in cylindrically symmetric traps. As an application,

we are able to compute many excitation modes by directly solving the

Bogoliubov-De Gennes equations. We explore the behavior of the excited modes in

different trap geometries. We use these results to calculate the quantum

depletion of the condensate by a combination of a computation of the exact

modes and the use of a local density approximation.

\\ ( http://arXiv.org/abs/cond-mat/0605409 , 69kb)

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

\\

Paper: cond-mat/0605410

Date: Tue, 16 May 2006 12:27:02 GMT (22kb)

Title: The Hall effect of dipole chain in one dimensional Bose-Einstein

condensation

Authors: Tieyan Si, Yue Yu

Comments: 4 pages

Subj-class: Mesoscopic Systems and Quantum Hall Effect; Statistical Mechanics

\\

We find a breather behavior of the dipole chain, this breather excitation

obey fractional statistics, it could be an experimental quantity to detect

anyon. A Hall effect of magnetic monopole in a dipole chain of ultracold

molecules is also presented, we show that this Hall effect can induce the flip

of magnetic dipole chain.

\\ ( http://arXiv.org/abs/cond-mat/0605410 , 22kb)

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

\\

Paper: cond-mat/0605412

Date: Tue, 16 May 2006 13:33:05 GMT (146kb)

Title: Solitons in coupled atomic-molecular Bose-Einstein condensates in a trap

Authors: B. Oles and K. Sacha

Comments: 7 pages, 7 figures

Subj-class: Other; Statistical Mechanics

\\

We consider coupled atomic-molecular Bose-Einstein condensate system in a

quasi-one-dimensional trap. In the vicinity of a Feshbach resonance the system

can reveal soliton-like behavior. We analyze bright soliton solutions for the

system in the trap and in the presence of the interactions between particles.

We show that with increasing number of particles in the system two bright

soliton solutions start resembling dark soliton profiles known in an atomic

Bose-Einstein condensate with repulsive interactions between atoms. We analyze

also methods for experimental preparation and detection of the soliton states.

\\ ( http://arXiv.org/abs/cond-mat/0605412 , 146kb)

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

\\

Paper: cond-mat/0605413

Date: Tue, 16 May 2006 13:54:45 GMT (26kb)

Title: Collective mode damping and viscosity in a 1D unitary Fermi gas

Authors: M. Punk, W. Zwerger

Comments: 9 pages, 3 figures, submitted to New J. Phys

Subj-class: Statistical Mechanics; Superconductivity

\\

We calculate the damping of the Bogoliubov-Anderson mode in a one-dimensional

two-component attractive Fermi gas for arbitrary coupling strength within a

quantum hydrodynamic approach. Using the Bethe-Ansatz solution of the 1D

BCS-BEC crossover problem, we derive analytic results for the viscosity

covering the full range from a Luther-Emery liquid of weakly bound pairs to a

Lieb-Liniger gas of strongly bound bosonic dimers. At the unitarity point, the

system is a Tonks-Girardeau gas with a universal constant $\alpha_{\zeta}=0.38$

in the viscosity $\zeta=\alpha_{\zeta}\hbar n$ for T=0. For the trapped case,

we calculate the Q-factor of the breathing mode and show that the damping

provides a sensitive measure of temperature in 1D Fermi gases.

\\ ( http://arXiv.org/abs/cond-mat/0605413 , 26kb)

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

\\

Paper: cond-mat/0605419

Date: Tue, 16 May 2006 17:57:01 GMT (114kb)

Title: Interacting Bose gases in quasi-one dimensional optical lattices

Authors: M. A. Cazalilla, A. F. Ho, and T. Giamarchi

Comments: 55 pages + 5 EPS figures; submitted to NJP

Subj-class: Mesoscopic Systems and Quantum Hall Effect; Statistical Mechanics

\\

We study a two-dimensional array of coupled one-dimensional (1D) tubes of

interacting bosons. Such systems can be produced by loading ultra-cold atoms in

anisotropic optical lattices. We investigate the effects of coupling the tubes

via hopping of the bosons (i.e. Josephson coupling). In the absence of a

periodic potential along the tubes, or when such potential is incommensurate

with the boson density, the system undergoes a transition from an array of

incoherent Tomonaga-Luttinger liquids at high temperature to an anisotropic

Bose-Einstein condensate (BEC), at low temperature. We determine the transition

temperature and long wave-length excitations of the BEC. In addition to the

usual gapless (Goldstone) mode found in standard superfluids, we also find a

gapped mode associated with fluctuations of the amplitude of the order

parameter. When a commensurate periodic potential is applied along the tubes,

they can become 1D Mott insulators. Intertube hopping leads to a deconfinement

quantum phase transition between the 1D Mott insulators and the anisotropic

BEC. We also take into account the finite size of the gas tubes as realized in

actual experiments. We map out the phase diagram of the quasi-1D lattice and

compare our results with the existing experiments on such systems.

\\ ( http://arXiv.org/abs/cond-mat/0605419 , 114kb)

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

\\

Paper: cond-mat/0605005

replaced with revised version Tue, 16 May 2006 01:37:43 GMT (50kb)

Title: Phase Transition in Imbalanced Fermion Superfluids

Authors: Heron Caldas

Comments: This is an invited contribution to a book titled "Pairing beyond BCS

Theory in Fermionic Systems" (Mark Alford, John Clark and Armen Sedrakian,

eds.), to be published by World Scientific. 3 figures, 12 pages, added more

references

Subj-class: Superconductivity; Strongly Correlated Electrons

\\ ( http://arXiv.org/abs/cond-mat/0605005 , 50kb)

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

\\

Paper: quant-ph/0605139

Date: Tue, 16 May 2006 14:38:26 GMT (98kb)

Title: Decay by tunneling of Bosonic and Fermionic Tonks-Girardeau Gases

Authors: A. del Campo, F. Delgado, G. Garcia-Calderon, J. G. Muga, and M. G.

Raizen

\\

We study the tunneling dynamics of bosonic and fermionic Tonks-Girardeau

gases from a hard wall trap, in which one of the walls is substituted by a

delta potential. Using the Fermi-Bose map, the decay of the probability to

remain in the trap is studied as a function of both the number of particles and

the intensity of the end-cap delta laser. The fermionic gas is shown to be a

good candidate to study deviations of the non-exponential decay of the

single-particle type, whereas for the bosonic case a novel regime of

non-exponential decay appears due to the contributions of different resonances

of the trap.

\\ ( http://arXiv.org/abs/quant-ph/0605139 , 98kb)

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

\\

Paper: physics/0605134

Date: Tue, 16 May 2006 11:22:50 GMT (100kb)

Title: Exploring the van der Waals Atom-Surface attraction in the nanometric

range

Authors: Mich\`{e}le Fichet (LPL), Gabriel Dutier (LPL), Alexander Yarovitski

(LPL), Petko Todorov (LPL), Ismah\`{e}ne Hamdi (LPL), Isabelle Maurin (LPL),

Solomon Saltiel (LPL), David Sarkisyan (IPR), Marie-Pascale Gorza (LPL),

Daniel Bloch (LPL), Martial Ducloy (LPL)

Comments: submitted as LS10371

Proxy: ccsd ccsd-00069106

Subj-class: Atomic Physics

\\

The van der Waals atom-surface attraction, scaling as C3 z-3 for z the

atom-surface distance, is expected to be valid for ~ 1-1000 nm, covering 8-10

orders of magnitudes in the interaction energy. Thanks to a Cs vapor nanocell,

we analyze the spectroscopic modifications induced by the atom-surface

attraction on the 6P3/2->6D5/2 transition. The C3 value, extracted

independently for various thicknesses ranging from 40 nm to 130 nm, is found to

be independent of the thickness. It agrees, but only within a factor of 2, with

an elementary theoretical prediction, whose validity is discussed.

\\ ( http://arXiv.org/abs/physics/0605134 , 100kb)

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

\\

Paper (*cross-listing*): nlin.PS/0605032

Date: Tue, 16 May 2006 09:27:06 GMT (551kb)

Title: Stable circulation modes in a dual-core matter-wave soliton laser

Authors: Peter Y. P. Chen (School of Mechanical and Manufacturing Engineering,

University of New South Wales, Sydney, Australia) and Boris A. Malomed

(Department of Interdisciplinary Studies, School of Electrical Engineering,

Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel)

Comments: J. of Physics B: At. Mol. Opt. Physics, in press

Subj-class: Pattern Formation and Solitons; Soft Condensed Matter

\\

We consider a model of a matter-wave laser generating a periodic array of

solitary-wave pulses. The system, a general version of which was recently

proposed in Ref. [5], is composed of two parallel tunnel-coupled cigar-shaped

traps (a reservoir and a lasing cavity), solitons being released through a

valve at one edge of the cavity. We report a stable lasing mode accounted for

by circulations of a narrow soliton in the cavity, which generates an array of

strong pulses (with 1,000 - 10,000 atoms in each, the array's duty cycle ~ 30%)

when the soliton periodically hits the valve.

\\ ( http://arXiv.org/abs/nlin/0605032 , 551kb)

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

\\

Paper (*cross-listing*): nlin.PS/0605035

Date: Tue, 16 May 2006 18:38:53 GMT (336kb)

Title: Stationary localized modes in the quintic nonlinear Schrodinger equation

with a periodic potential

Authors: G. L. Alfimov, V. V. Konotop, P. Pacciani

Comments: 4 pages, 5 figures

Subj-class: Pattern Formation and Solitons; Other

\\

We consider one-dimensional quintic nonlinear Schr\"{o}dinger equation with a

periodic potential. In the case of attractive nonlinearity we deduce sufficient

condition for collapse. We show that there exist spatially localized solutions

with arbitrarily large number of particles. We study such solutions in the

semi-infinite gap (attractive case) and in the first gap (attractive and

repulsive cases) and show that a nonzero minimum value of the number of

particles is necessary for a mode to be created. In the limit of large negative

frequencies (attractive case) we observe ``quantization'' of the number of

particles of the stationary modes. Such solutions can be interpreted as coupled

``Townes'' solitons and appear to be stable. The modes in the first gap have

numbers of particles infinitely growing with frequencies approaching one of the

gap edges, what is explained by the power decay of the modes. Gap solitons are

found to be unstable.

\\ ( http://arXiv.org/abs/nlin/0605035 , 336kb)

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

\\

Paper: cond-mat/0601147

replaced with revised version Wed, 17 May 2006 08:51:37 GMT (889kb)

Title: LOFF Pairing vs. Breached Pairing in Asymmetric Fermion Superfluids

Authors: Lianyi He, Meng Jin and Pengfei Zhuang

Comments: 12 pages, 13 figures, version to appear in Physical Review B

Subj-class: Superconductivity

\\ ( http://arXiv.org/abs/cond-mat/0601147 , 889kb)

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

\\

Paper: cond-mat/0601302

replaced with revised version Tue, 16 May 2006 21:24:54 GMT (20kb)

Title: Quantum magnetism with multicomponent polar molecules in an optical

lattice

Authors: Ryan Barnett, Dmitry Petrov, Mikhail Lukin, Eugene Demler

Subj-class: Strongly Correlated Electrons

Journal-ref: Phys. Rev. Lett. 96, 190401 (2006)

\\ ( http://arXiv.org/abs/cond-mat/0601302 , 20kb)

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

\\

Paper: cond-mat/0603458

replaced with revised version Wed, 17 May 2006 16:17:07 GMT (100kb)

Title: Dynamic response of one-dimensional interacting fermions

Authors: M. Pustilnik, M. Khodas, A. Kamenev, L.I. Glazman

Subj-class: Mesoscopic Systems and Quantum Hall Effect; Strongly Correlated

Electrons

Journal-ref: Phys. Rev. Lett. 96, 196405 (2006)

DOI: 10.1103/PhysRevLett.96.196405

\\ ( http://arXiv.org/abs/cond-mat/0603458 , 100kb)

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

\\

Paper: cond-mat/0605138

replaced with revised version Wed, 17 May 2006 13:49:25 GMT (52kb)

Title: Landau functions for non-interacting bosons

Authors: Andreas Sinner, Florian Schuetz, and Peter Kopietz

Comments: 4 pages, 4 figures; references added and text slightly changed

Subj-class: Statistical Mechanics

\\ ( http://arXiv.org/abs/cond-mat/0605138 , 52kb)

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

\\

Paper (*cross-listing*): hep-th/0510238

replaced with revised version Wed, 17 May 2006 11:40:35 GMT (10kb)

Title: Casimir forces in Bose-Einstein condensates: finite size effects in

three-dimensional rectangular cavities

Authors: Ariel Edery

Comments: 12 pages; no figures; v.2: version accepted for publication in JSTAT

Subj-class: High Energy Physics - Theory; Statistical Mechanics

\\ ( http://arXiv.org/abs/hep-th/0510238 , 10kb)

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

\\

Paper: physics/0605152

Date: Wed, 17 May 2006 16:59:14 GMT (11kb)

Title: Five Frequently Fatal Freshman Physics Fantasies

Authors: Michael Courtney, Norm Althausen, and Amy Courtney

Comments: 3 pages, submitted to The Physics Teacher

Subj-class: Physics Education

\\

This article describes five common student misconceptions about succeeding in

college-level Physics courses: the miracle finish, the soft hearted professor,

an extension of high school, weak areas won't be tested, and passing is more

important than learning. These fantasies are unique to neither Physics nor

freshman, but the challenge of learning Physics brings more certain negative

consequences to students retaining these attitudes. Ascribing these student

misconceptions to freshmen acknowledges that they diminish with increasing

academic maturity.

\\ ( http://arXiv.org/abs/physics/0605152 , 11kb)

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

\\

Paper: cond-mat/0605440

Date: Thu, 18 May 2006 15:54:43 GMT (373kb)

Title: Detecting the breached pair phase in a polarized ultracold Fermi gas

Authors: W. Yi and L.-M. Duan

Comments: 4 pages, 3 figures

Subj-class: Other

\\

We propose a method for the experimental detection of a new quantum phase,

the breached pair state, in a strongly interacting ultracold Fermi gas with

population imbalance. We show that through the time-of-flight Raman imaging,

the presence of such a phase can be unambiguously determined with a measurement

of the momentum-space phase separation of the minority spin component. To guide

the experimental efforts, the momentum-space density profiles are calculated

under typical experimental conditions.

\\ ( http://arXiv.org/abs/cond-mat/0605440 , 373kb)

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

\\

Paper: cond-mat/0605459

Date: Thu, 18 May 2006 11:58:13 GMT (45kb)

Title: Critical Velocities for Energy Dissipation from Periodic Motions of

Impurity in Bose-Einstein Condensates

Authors: Jun Suzuki

Comments: 6 pages, 3 figures

Subj-class: Statistical Mechanics; Other

\\

A phenomenon of energy dissipation in Bose-Einstein condensates is studied

based on a microscopic model for the motion of impurity. Critical velocities

for onset of energy dissipation are obtained for periodic motions, such as a

dipole-like oscillation and a circular motion. The first example is similar to

a series of MIT group experiments settings where the critical velocity was

observed much below the Landau critical velocity. The appearance of the smaller

values for the critical velocity is also found in our model, even in the

homogeneous condensate in the thermodynamic limit. This suggests that the

landau criterion be reexamined in the absence of quantized vortices in the bulk

limit.

\\ ( http://arXiv.org/abs/cond-mat/0605459 , 45kb)

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

\\

Paper: cond-mat/0605163

replaced with revised version Thu, 18 May 2006 14:33:31 GMT (156kb)

Title: Mean-field phase diagram of disordered bosons in a lattice at non-zero

temperature

Authors: K.V.Krutitsky, A.Pelster and R.Graham

Subj-class: Other; Disordered Systems and Neural Networks

\\ ( http://arXiv.org/abs/cond-mat/0605163 , 156kb)

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

\\

Paper: cond-mat/0605419

replaced with revised version Thu, 18 May 2006 17:30:17 GMT (114kb)

Title: Interacting Bose gases in quasi-one dimensional optical lattices

Authors: M. A. Cazalilla, A. F. Ho, and T. Giamarchi

Comments: 55 pages + 5 EPS figures; submitted to NJP; v2: reference added

Subj-class: Mesoscopic Systems and Quantum Hall Effect; Statistical Mechanics

\\ ( http://arXiv.org/abs/cond-mat/0605419 , 114kb)

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

\\

Paper: quant-ph/0605163

Date: Thu, 18 May 2006 19:23:40 GMT (617kb)

Title: Quantum Information Processing in Optical Lattices and Magnetic

Microtraps

Authors: Philipp Treutlein, Tilo Steinmetz, Yves Colombe, Peter Hommelhoff,

Jakob Reichel, Markus Greiner, Olaf Mandel, Arthur Widera, Tim Rom, Immanuel

Bloch, and Theodor W. H\"ansch

Comments: 15 pages, 11 figures

\\

We review our experiments on quantum information processing with neutral

atoms in optical lattices and magnetic microtraps.

Atoms in an optical lattice in the Mott insulator regime serve as a large

qubit register. A spin-dependent lattice is used to split and delocalize the

atomic wave functions in a controlled and coherent way over a defined number of

lattice sites. This is used to experimentally demonstrate a massively parallel

quantum gate array, which allows the creation of a highly entangled many-body

cluster state through coherent collisions between atoms on neighbouring lattice

sites.

In magnetic microtraps on an atom chip, we demonstrate coherent manipulation

of atomic qubit states and measure coherence lifetimes exceeding one second at

micron-distance from the chip surface. We show that microwave near-fields on

the chip can be used to create state-dependent potentials for the

implementation of a quantum controlled phase gate with these robust qubit

states. For single atom detection and preparation, we have developed high

finesse fiber Fabry-Perot cavities and integrated them on the atom chip. We

present an experiment in which we detected a very small number of cold atoms

magnetically trapped in the cavity using the atom chip.

\\ ( http://arXiv.org/abs/quant-ph/0605163 , 617kb)

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

\\

Paper: physics/0605159

Date: Thu, 18 May 2006 09:35:10 GMT (568kb)

Title: Collisional shifts in optical-lattice atom clocks

Authors: Y. B. Band and A. Vardi

Comments: 15 pages, 11 figures

Subj-class: Atomic Physics; General Physics

\\

We theoretically study the effects of elastic collisions on the determination

of frequency standards via Ramsey fringe spectroscopy in optical-lattice atom

clocks. Interparticle interactions of bosonic atoms in multiply-occupied

lattice sites can cause a linear frequency shift, as well as generate

asymmetric Ramsey fringe patterns and reduce fringe visibility due to

interparticle entanglement. We propose a method of reducing these collisional

effects in an optical lattice by introducing a phase difference of $\pi$

between the Ramsey driving fields in adjacent sites. This configuration

suppresses site to site hopping due to interference of two tunneling pathways,

without degrading fringe visibility. Consequently, the probability of double

occupancy is reduced, leading to cancellation of collisional shifts.

\\ ( http://arXiv.org/abs/physics/0605159 , 568kb)

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

\\

Paper: cond-mat/0605486

Date: Fri, 19 May 2006 13:47:16 GMT (205kb)

Title: The two-site Bose--Hubbard model

Authors: J. Links, A. Foerster, A. Tonel and G. Santos

Comments: 10 pages, 5 figures, submitted for publication in Annales Henri

Poincare

Subj-class: Other

\\

The two-site Bose--Hubbard model is a simple model used to study Josephson

tunneling between two Bose--Einstein condensates. In this work we give an

overview of some mathematical aspects of this model. Using a classical

analysis, we study the equations of motion and the level curves of the

Hamiltonian. Then, the quantum dynamics of the model is investigated using

direct diagonalisation of the Hamiltonian. In both of these analyses, the

existence of a threshold coupling between a delocalised and a self-trapped

phase is evident, in qualitative agreement with experiments. We end with a

discussion of the exact solvability of the model via the algebraic Bethe

ansatz.

\\ ( http://arXiv.org/abs/cond-mat/0605486 , 205kb)

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

\\

Paper: cond-mat/0605494

Date: Fri, 19 May 2006 17:04:03 GMT (15kb)

Title: Response functions and superfluid density in a weakly interacting Bose

gas with non-quadratic dispersion

Authors: Jonathan Keeling

Comments: 4 pages, 2 figures

Subj-class: Mesoscopic Systems and Quantum Hall Effect

\\

Motivated by the experimental search for Bose condensation of quasiparticles

in semiconductors, the response functions of a weakly interacting Bose gas,

with isotropic but non-quadratic dispersion, are considered. Non-quadratic

dispersion modifies the definition of particle current, and leads to modified

sum rules for the current-current response function. The effect of these

modifications on the Berezhinski-Kosterlitz-Thouless transition is discussed.

\\ ( http://arXiv.org/abs/cond-mat/0605494 , 15kb)

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

\\

Paper: cond-mat/0601314

replaced with revised version Fri, 19 May 2006 18:32:31 GMT (447kb)

Title: Profiles of near-resonant population-imbalanced trapped Fermi gases

Authors: Theja N. De Silva, Erich J. Mueller

Comments: 4 pages, 5 Figures, Published version

Subj-class: Other

Journal-ref: Phys. Rev. A 73, 051602(R) (2006)

DOI: 10.1103/PhysRevA.73.051602

\\ ( http://arXiv.org/abs/cond-mat/0601314 , 447kb)

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

\\

Paper: quant-ph/0605168

Date: Thu, 18 May 2006 21:34:46 GMT (318kb)

Title: Field autocorrelations in electromagnetically induced transparency:

Effects of a squeezed probe field

Authors: P. Barberis-Blostein

\\

The interaction of a quantized field with three-level atoms in $\Lambda$

configuration inside a two mode cavity is analyzed. We calculate the stationary

quadrature noise spectrum of the field outside the cavity in the case where the

input probe field is in a squeezed state and the atoms show electromagnetically

induced transparency (EIT). If the Rabi frequencies of both dipole transitions

of the atoms are different from zero, we show that the output probe field have

four maxima of squeezing absorption. We show that in some cases two of these

frequencies can be very close to the transition frequency of the atom, in a

region where the mean value of the field entering the cavity is hardly altered.

Furthermore, part of the absorbed squeezing of the probe field is transfered to

the pump field. For some conditions this transfer of squeezing can be complete.

\\ ( http://arXiv.org/abs/quant-ph/0605168 , 318kb)

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

\\

Paper: quant-ph/0602048

replaced with revised version Fri, 19 May 2006 16:34:39 GMT (10kb)

Title: Single-Site Entanglement of Fermions at a Quantum Phase Transition

Authors: Daniel Larsson and Henrik Johannesson

Comments: 4 pages, no figure. Published version

Subj-class: Quantum Physics; Strongly Correlated Electrons

Journal-ref: Phys. Rev. A 73, 042320 (2006)

\\ ( http://arXiv.org/abs/quant-ph/0602048 , 10kb)

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

Till next week,

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/ -------------------------------------------------------------------------Received on Mon May 22 2006 - 18:04:39 EST

*
This archive was generated by hypermail 2.2.0
: Thu May 08 2008 - 11:51:41 EST
*