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

Date: Thu, 20 Dec 2007 22:52:44 +1000

Date: Thu, 20 Dec 2007 22:52:44 +1000

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

Hi all,

With this message I'm now only four days behind schedule... another busy week

with 31 new preprints and 9 replacements.

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arXiv:0711.4840

Date: Thu, 29 Nov 2007 22:13:33 GMT (507kb)

Title: Entanglement, Non-linear Dynamics and Heisenberg Limit with

Bose-Einstein Condensates

Authors: L. Pezze' and A. Smerzi

Categories: quant-ph

Comments: 4 pages, 2 figures

\\

We introduce a condition which is sufficient for particle-entanglement and

necessary and sufficient for sub shot-noise phase sensitivity in the estimation

of a collective rotation angle $\theta$. The connection is provided by the

Fisher information which is a simple measure of the statistical distance among

quantum states. We study the production of this \emph{useful} entanglement by

the non-linear evolution of two decoupled Bose-Einstein condensates or trapped

ions.

\\ ( http://arxiv.org/abs/0711.4840 , 507kb)

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arXiv:0711.4870

Date: Fri, 30 Nov 2007 04:38:31 GMT (59kb)

Title: Bright bichromatic entanglement and quantum dynamics of sum frequency

generation

Authors: M.K. Olsen, A.S. Bradley

Categories: quant-ph

\\

We investigate the quantum properties of the well-known process of sum

frequency generation, showing that it is potentially a very useful source of

non-classical states of the electromagnetic field, some of which are not

possible with the more common techniques. We show that it can produce

quadrature squeezed light, bright bichromatic entangled states and symmetric

and asymmetric demonstrations of the Einstein-Podolsky-Rosen paradox. We also

show that the semiclassical equations totally fail to describe the mean-field

dynamics when the cavity is strongly pumped.

\\ ( http://arxiv.org/abs/0711.4870 , 59kb)

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arXiv:0711.4960

Date: Fri, 30 Nov 2007 15:45:19 GMT (253kb)

Title: Coherent backscattering of light from saturated atoms

Authors: Vyacheslav Shatokhin, Thomas Wellens, Cord M\"uller, and Andreas

Buchleitner

Categories: quant-ph

Comments: 5 pages, 4 figures

\\

We survey recent progress achieved in understanding the impact of inelastic

processes on coherent backscattering of light from cold atoms that are

saturated by a powerful laser field.

\\ ( http://arxiv.org/abs/0711.4960 , 253kb)

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arXiv:0711.4786 (*cross-listing*)

Date: Thu, 29 Nov 2007 17:55:32 GMT (34kb)

Title: Discovery of exceptional points in the Bose-Einstein condensation of

gases with attractive 1/r-interaction

Authors: Holger Cartarius, J\"org Main, G\"unter Wunner

Categories: nlin.CD quant-ph

Comments: 9 pages, 6 figures

\\

The extended Gross-Pitaevskii equation for the Bose-Einstein condensation of

gases with attractive 1/r-interaction has a second solution which is born

together with the ground state in a tangent bifurcation. At the bifurcation

point both states coalesce, i.e., the energies and the wave functions are

identical. We investigate the bifurcation point in the context of exceptional

points, a phenomenon known for linear non-Hermitian Hamiltonians. We point out

that the mean field energy, the chemical potential, and the wave functions show

the same behavior as an exceptional point in a linear, non-symmetric system.

The analysis of the analytically continued Gross-Pitaevskii equation reveals

complex waves at negative scattering lengths below the tangent bifurcation.

These solutions are interpreted as a decay of the condensate caused by an

absorbing potential.

\\ ( http://arxiv.org/abs/0711.4786 , 34kb)

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arXiv:0711.4846

Date: Thu, 29 Nov 2007 22:44:41 GMT (154kb)

Title: Collisional Control of Ground State Polar Molecules and Universal

Dipolar Scattering

Authors: Christopher Ticknor

Categories: physics.atom-ph

Comments: 4 pages, 2 figures

\\

We explore the impact of the short range interaction on the scattering of

ground state polar molecules, and study the transition from a weak to strong

dipolar scattering over an experimentally reasonable range of energies and

electric field values. In the strong dipolar limit, the scattering scales with

respect to a dimensionless quantity defined by mass, induced dipole moment, and

collision energy. The scaling has implications for all quantum mechanical

dipolar scattering, and therefore this universal dipolar scaling provides

estimates of scattering cross sections for any dipolar system.

\\ ( http://arxiv.org/abs/0711.4846 , 154kb)

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arXiv:0711.4636 (*cross-listing*)

Date: Thu, 29 Nov 2007 00:57:33 GMT (67kb)

Title: Testing Atom and Neutron Neutrality with Atom Interferometry

Authors: Asimina Arvanitaki, Savas Dimopoulos, Andrew A. Geraci, Jason Hogan,

and Mark Kasevich

Categories: hep-ph hep-ex hep-th physics.atom-ph

Comments: 4 pages, 2 figures, to be submitted for publication in PRL

\\

We propose an atom-interferometry experiment based on the scalar

Aharonov-Bohm effect which detects an atom charge at the 10^{-28}e level, and

improves the current laboratory limits by 8 orders of magnitude. This setup

independently probes neutron charges down to 10^{-28}e, 7 orders of magnitude

below current bounds.

\\ ( http://arxiv.org/abs/0711.4636 , 67kb)

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arXiv:0712.0037

Date: Sat, 1 Dec 2007 01:49:28 GMT (149kb)

Title: Comparative study of strong coupling theories of a trapped Fermi gas at

unitarity

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

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

Comments: 4 pages and 3 figures; To be submitted

\\

We present a systematic comparison of the most recent thermodynamic

measurements of a trapped Fermi gas at unitarity, with the predictions from

available strong coupling theories, including quantum Monte Carlo (MC)

simulations. The exceptional accuracy of the experimental data, of the order of

a few percent, allows a precision test of different many-body approaches. We

find that the simple Nozieres and Schmitt-Rink treatment of fluctuations is in

excellent agreement with the experimental data and available MC calculations at

unitarity.

\\ ( http://arxiv.org/abs/0712.0037 , 149kb)

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arXiv:0712.0044

Date: Sat, 1 Dec 2007 04:09:24 GMT (5kb)

Title: Quantum Statistical Transition

Authors: Tao Wang

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

Comments: 5 pages no figures

\\

By analyzing the BCS-BEC crossover, I found that because of the pairing

interactions,a continuous family of quantum statistics interpolating between

fermions and bosons is possible, although it seems incapable to construct

reasonable wave function.

\\ ( http://arxiv.org/abs/0712.0044 , 5kb)

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arXiv:0712.0205

Date: Mon, 3 Dec 2007 14:01:20 GMT (9kb)

Title: Self-consistent equations of unitary fermion thermodynamics with elusive

non-Gaussian correlations

Authors: Ji-sheng Chen, Jia-rong Li, Yan-ping Wang, Xiang-jun Xia

Categories: cond-mat.stat-mech

Comments: 5 pages

\\

We study the dynamical high order perturbation and statistically nonlinear

infrared fluctuation/correlation role on the unitary fermion gas

thermodynamics. Due to the significant quantum levels rearrangement, the

spontaneously generated entropy departing from the mean field theory formalism

leads to the concise analytical thermodynamical expressions. With the exact

scaling equation of state, the dimensionless virial coefficients are calculated

up to the fourth order and are found to be proportional to those of the ideal

non-interacting quantum gas with integer ratios. Intriguingly, contrary to

those for the ideal bosons ($a^{(0)}_2=-\frac{1}{2 \sqrt{2} g}$) or fermions

($a^{(0)}_2=\frac{1}{2 \sqrt{2} g}$) in the high temperature weak degenerate

Boltzmann regime, the second virial coefficient of unitary gas is equal to zero

$a_2=0$. At the BCS-BEC crossover point, the novel quantum thermodynamics

manifests the famous pure classical Boyle characteristic by keeping up to the

second virial.

\\ ( http://arxiv.org/abs/0712.0205 , 9kb)

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arXiv:0712.0251

Date: Mon, 3 Dec 2007 10:31:35 GMT (41kb)

Title: Superfluid, solid, supersolid and quantum phase transitions on bipartite

lattices and its applications on ultra-cold atoms on optical lattices, adatom

adsorption on substrates and high temperature superconductors

Authors: Jinwu Ye

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

Comments: 12 pages, 5 figures, REVTEX4, long version of cond-mat/0503113

\\

We study phases such as superfluid, solid, supersolid and quantum phase

transitions in a unified scheme in extended boson Hubbard models slightly away

from half filling on bipartite optical lattices such as honeycomb and square

lattice. We also map out its global phase diagram at $ T=0 $. We find that in

the translational symmetry breaking side, different kinds of supersolids are

generic possible states slightly away from half filling. We propose a new kind

of supersolid: valence bond supersolid. We show that the quantum phase

transitions from solids to supersolids driven by a chemical potential are in

the same universality class as that from a Mott insulator to a superfluid,

therefore have exact exponents $ z=2, \nu=1/2, \eta=0 $ with a logarithmic

correction. Comparisons with previous quantum Monte-Carlo (QMC) simulations on

a square lattice are made. Implications on possible future QMC simulations are

given. All these phases and phase transitions can be realized in ultra-cold

atoms loaded on optical bipartite lattices. Then we use our results to study

the reentrant "superfluid" in a narrow region of coverages in the second layer

of $^{4}He $ adsorbed on graphite and the low temperature phase diagram of

Hydrogen physisorbed on Krypton-preplated graphite ($ H_2 $/Kr/graphite) near

half filling. We suggest that $^{4}He $ and $ H_2 $ lattice supersolids maybe

responsible for the experimental signals in the two systems. Finally, we

suggest Cooper supersolid is repressible for the phase diagram of $ La_{2-x}

Ba_{x} Cu O_{4} $ near $ x=1/8 $.

\\ ( http://arxiv.org/abs/0712.0251 , 41kb)

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arXiv:0712.0311

Date: Mon, 3 Dec 2007 15:14:09 GMT (802kb,D)

Title: Exploring the growth of correlations in a quasi one-dimensional trapped

Bose gas

Authors: M. Eckart, R. Walser and W.P. Schleich

Categories: cond-mat.mes-hall

Comments: 36 pages, 21 color pdf/jpeg figures, submitted to NJP

\\

Phase correlations, density fluctuations and three-body loss rates are

relevant for many experiments in quasi one-dimensional geometries. Extended

mean-field theory is used to evaluate correlation functions up to third order

for a quasi one-dimensional trapped Bose gas at zero and finite temperature. At

zero temperature and in the homogeneous limit, we also study the transition

from the weakly correlated Gross-Pitaevskii regime to the strongly correlated

Tonks-Girardeau regime analytically. We compare our results with the exact

Lieb-Liniger solution for the homogeneous case and find good agreement up to

the cross-over regime.

\\ ( http://arxiv.org/abs/0712.0311 , 802kb)

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arXiv:0712.0348

Date: Mon, 3 Dec 2007 17:12:06 GMT (166kb)

Title: Entanglement renormalization and topological order

Authors: Miguel Aguado, Guifre Vidal

Categories: cond-mat.str-el

Comments: 6 pages, 17 eps files

\\

The multi-scale entanglement renormalisation ansatz (MERA) is argued to

provide a natural description for topological states of matter. The case of

Kitaev's toric code is analyzed in detail and shown to possess a remarkably

simple MERA description leading to distillation of the topological degrees of

freedom at the top of the tensor network. Kitaev states on an infinite lattice

are also shown to be a fixed point of the RG flow associated with entanglement

renormalization. All these results generalize to arbitrary quantum double

models.

\\ ( http://arxiv.org/abs/0712.0348 , 166kb)

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arXiv:0712.0355

Date: Mon, 3 Dec 2007 18:08:50 GMT (40kb)

Title: Bright and dark solitary waves in a one-dimensional spin-polarized gas

of fermionic atoms with p-wave interactions in a hard-wall trap

Authors: M.D. Girardeau, E.M. Wright

Categories: cond-mat.other

Comments: 4 pages+, 3 figures, revtex4. Submitted to PRL

\\

In this paper we elucidate the physics underlying the fact that both bright

and dark solitary waves can arise in a one-dimensional spin-polarized gas of

fermionic atoms with attractive three-dimensional p-wave interactions in a

hard-wall trap. This is possible since the one-dimensional fermion system can

be mapped to a system of bosons described by the Lieb-Liniger model with either

repulsive or attractive delta-function interactions which can support solitary

waves.

\\ ( http://arxiv.org/abs/0712.0355 , 40kb)

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arXiv:0712.0376

Date: Mon, 3 Dec 2007 20:38:08 GMT (6kb)

Title: Analog gravity with spinor Bose-Einstein condensates

Authors: E. Calzetta

Categories: cond-mat.other

Comments: 4 pages

\\

It is well known that both a particle with spin and a quantum field in a

Bianchi type IX Universe are both related to the quantum mechanical top. In

this paper we will combine these insights to show that the dynamics of a cold

gas of noninteracting atoms with total momentum F=1 may be used to explore the

behavior of quantum matter near a cosmological singularity.

\\ ( http://arxiv.org/abs/0712.0376 , 6kb)

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arXiv:0711.4840 (*cross-listing*)

Date: Thu, 29 Nov 2007 22:13:33 GMT (507kb)

Date (revised v2): Fri, 30 Nov 2007 21:35:10 GMT (507kb)

Title: Entanglement, Non-linear Dynamics and Heisenberg Limit with

Bose-Einstein Condensates

Authors: L. Pezze' and A. Smerzi

Categories: quant-ph cond-mat.other

Comments: 4 pages, 2 figures

\\

We introduce a condition which is sufficient for particle-entanglement and

necessary and sufficient for sub shot-noise phase sensitivity in the estimation

of a collective rotation angle $\theta$. The connection is provided by the

Fisher information which is a simple measure of the statistical distance among

quantum states. We study the production of this \emph{useful} entanglement by

the non-linear evolution of two decoupled Bose-Einstein condensates or trapped

ions.

\\ ( http://arxiv.org/abs/0711.4840 , 507kb)

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arXiv:0711.4954 (*cross-listing*)

Date: Fri, 30 Nov 2007 15:11:37 GMT (238kb)

Title: The Vacuum Fluctuation Theorem: Exact Schroedinger Equation via

Nonequilibrium Thermodynamics

Authors: Gerhard Groessing

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

Comments: 39 pages

\\

By assuming that a particle of energy hbar.omega is actually a dissipative

system maintained in a nonequilibrium steady state by a constant throughput of

energy (heat flow), the exact Schroedinger equation is derived, both for

conservative and nonconservative systems. Thereby, only universal properties of

oscillators and nonequilibrium thermostatting are used, such that a maximal

model independence of the hypothesised sub-quantum physics is guaranteed. It is

claimed that this represents the shortest derivation of the Schroedinger

equation from (modern) classical physics in the literature, and the only exact

one, too. Moreover, a "vacuum fluctuation theorem" is presented, with

particular emphasis on possible applications for a better understanding of

quantum mechanical nonlocal effects.

\\ ( http://arxiv.org/abs/0711.4954 , 238kb)

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arXiv:0712.0060

Date: Sat, 1 Dec 2007 09:15:45 GMT (36kb)

Title: Dark-State Polaritons for multi-component and stationary light fields

Authors: F. E. Zimmer, J. Otterbach, R. G. Unanyan, B. W. Shore, and M.

Fleischhauer

Categories: quant-ph

Comments: 5 pages, 2 figures

\\

We present a general scheme to determine the loss-free adiabatic

eigensolutions (dark-state polaritons) of the interaction of multiple probe

laser beams with a coherently driven atomic ensemble under conditions of

electromagnetically induced transparency. To this end we generalize the

Morris-Shore transformation to linearized Heisenberg-Langevin equations

describing the coupled light-matter system in the low excitation limit. In

particular a closed-loop double-V scheme is considered where two

counter-propagating control fields generate a quasi stationary pattern of two

counter-propagating probe fields, so-called stationary light. It is shown that

contrary to previous predictions there exists a single unique dark-state

polariton that obeys a simple propagation equation. In the case of a simple

lambda-type coupling scheme the generalized Morris-Shore transformation

reproduces the dark-state polariton solutions of slow light.

\\ ( http://arxiv.org/abs/0712.0060 , 36kb)

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arXiv:0712.0256

Date: Mon, 3 Dec 2007 10:47:27 GMT (155kb)

Title: Hamiltonian Design in Atom-Light Interactions with Rubidium Ensembles: A

Quantum Information Toolbox

Authors: S. R. de Echaniz, M. Koschorreck, M. Napolitano, M. Kubasik and M. W.

Mitchell

Categories: quant-ph

Comments: 6 pages, 4 figures

\\

We study the coupling between collective variables of atomic spin and light

polarization in an ensemble of cold 87Rb probed with polarized light. The

effects of multiple hyperfine levels manifest themselves as a rank-2 tensor

polarizability, whose irreducible components can be selected by means of probe

detuning. The D1 and D2 lines of Rb are explored and we identify different

detunings which lead to Hamiltonians with different symmetries for rotations.

As possible applications of these Hamiltonians, we describe schemes for spin

squeezing, quantum cloning, quantum memory, and measuring atom number.

\\ ( http://arxiv.org/abs/0712.0256 , 155kb)

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arXiv:0712.0428

Date: Tue, 4 Dec 2007 03:55:29 GMT (222kb)

Title: Experimentally accessible reentrant phase transitions in double-well

optical lattices

Authors: Ippei Danshita, Carlos A. R. Sa de Melo, Charles W. Clark

Categories: cond-mat.other

Comments: 4 pages, 5 figures

\\

We study the quantum phases of bosons confined in a combined potential of a

one-dimensional double-well optical lattice and a parabolic trap. We apply the

time-evolving block decimation method to the corresponding two-legged

Bose-Hubbard model. In the absence of a parabolic trap, the system of bosons in

the double-well optical lattice exhibits a reentrant quantum phase transition

between Mott insulator and superfluid phases at unit filling as the tilt of the

double-wells is increased. We show that the reentrant phase transition occurs

also in the presence of a parabolic trap and suggest that it can be detected in

experiments by measuring the matter-wave interference pattern.

\\ ( http://arxiv.org/abs/0712.0428 , 222kb)

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arXiv:0712.0431

Date: Tue, 4 Dec 2007 04:08:02 GMT (301kb)

Title: Spontaneous rotation in one-dimensional cold atoms

Authors: Akiyuki Tokuno, Masahiro Sato

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

Comments: 5 pages, 3 figures

\\

We theoretically study harmonically-trapped one-dimensional Bose gases (e.g.,

${}7{\rm Li}$, ${}^{23}{\rm Na}$, ${}^{39}{\rm K}$, ${}^{87}{\rm Rb}$, etc.)

with multi bands occupied, focusing on effects of higher-energy bands.

Combining the Ginzburg-Landau theory with the bosonization techniques, we

predict that the repulsive interaction between higher-band bosons and the

quantum fluctuation can induce the ground state with a finite angular momentum

around the trapped axis. In this state, the $Z_2$ reflection symmetry is

spontaneously broken.

\\ ( http://arxiv.org/abs/0712.0431 , 301kb)

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arXiv:0712.0557

Date: Tue, 4 Dec 2007 15:52:04 GMT (41kb)

Title: Kinetics of phase separation transition in cold-atom boson-fermion

mixtures

Authors: Dmitry Solenov and Dmitry Mozyrsky

Categories: cond-mat.mes-hall

Comments: 4 pages 1 figure

\\

We study the kinetics of the first order phase separation transition in

boson-fermion cold atom mixtures. At sufficiently low temperatures such a

transition is driven by quantum fluctuations responsible for the formation of

critical nuclei of a stable phase. Based on a microscopic description of

interacting boson-fermion mixtures we derive an effective action for the

critical droplet and obtain an asymptotic expression for the nucleation rate in

the vicinity of the phase transition and near the spinodal instability of the

mixed phase. We also discuss effects of dissipation which play a dominant role

close to the transition point, and identify the regimes where quantum

nucleation can be experimentally observed in cold atom systems.

\\ ( http://arxiv.org/abs/0712.0557 , 41kb)

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arXiv:0710.3768 (*cross-listing*)

Date: Fri, 19 Oct 2007 19:56:34 GMT (382kb)

Date (revised v2): Tue, 4 Dec 2007 17:16:12 GMT (410kb)

Title: Atom Interferometry tests of the isotropy of post-Newtonian gravity

Authors: Holger Mueller, Sheng-wey Chiow, Sven Herrmann, Steven Chu, and

Keng-Yeow Chung

Categories: gr-qc physics.atom-ph

Comments: Added outlook, corrected typos; to appear in PRL. 4 pages, 3 figures

\\

We present a test of the local Lorentz invariance of post-Newtonian gravity

by monitoring Earth's gravity with a Mach-Zehnder atom interferometer that

features a resolution of about 8*10^(-9)g/Hz^(1/2), the highest reported thus

far. Expressed within the standard model extension (SME) or Nordtvedt's

anisotropic universe model, the analysis limits four coefficients describing

anisotropic gravity at the ppb level and three others, for the first time, at

the 10ppm level. Using the SME we explicitly demonstrate how the experiment

actually compares the isotropy of gravity and electromagnetism.

\\ ( http://arxiv.org/abs/0710.3768 , 410kb)

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arXiv:0712.0717

Date: Wed, 5 Dec 2007 13:51:47 GMT (124kb)

Title: All-optical production of 7Li Bose-Einstein condensation using Feshbach

resonances

Authors: Noam Gross and Lev Khaykovich

Categories: physics.atom-ph

Comments: 5 pages, 5 figures

\\

We show an all-optical method of making 7Li condensate using tunability of

the scattering length in the proximity of a Feshbach resonance. We report the

observation of two new Feshbach resonances on |F = 1;mF = 0> state. The narrow

(broad) resonance of 7 G (34 G) width is detected at 831 +- 4 G (884 +4 -13 G).

Position of the scattering length zero crossing between the resonances is found

at 836 +- 4 G. The broad resonance is shown to be favorable for run away

evaporation which we perform in a crossed-beam optical dipole trap. Starting

directly form the phase space density of a magneto-optical trap we observe a

Bose-Einstein condensation threshold in less than 3 s of forced evaporation.

\\ ( http://arxiv.org/abs/0712.0717 , 124kb)

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arXiv:0712.0794

Date: Wed, 5 Dec 2007 18:14:52 GMT (807kb,D)

Title: A high-accuracy algorithm for designing arbitrary holographic atom traps

Authors: M. Pasienski and B. DeMarco

Categories: physics.atom-ph

Comments: version with high-resolution figures available at

http://research.physics.uiuc.edu/DeMarco/

\\

We report the realization of a new iterative Fourier-transform algorithm for

creating holograms that can diffract light into an arbitrary two-dimensional

intensity profile. We show that the predicted intensity distributions are

smooth with a fractional error from the target distribution at the percent

level. We demonstrate that this new algorithm outperforms the most frequently

used alternatives typically by one and two orders of magnitude in accuracy and

roughness, respectively. The techniques described in this paper outline a path

to creating arbitrary holographic atom traps in which the only remaining hurdle

is physical implementation.

\\ ( http://arxiv.org/abs/0712.0794 , 807kb)

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arXiv:0712.0867

Date: Thu, 6 Dec 2007 05:36:27 GMT (28kb)

Title: On Non-Relativistic Conformal Field Theory and Trapped Atoms: Virial

Theorems and the State-Operator Correspondence in Three Dimensions

Authors: Thomas Mehen (Duke U.)

Categories: cond-mat.other

Comments: 23 pages, 3 .ps figures

\\

The field theory of nonrelativistic fermions interacting via contact

interactions can be used to calculate the properties of few-body systems of

cold atoms confined in harmonic traps. The state-operator correspondence of

Non-Relativistic Conformal Field Theory (NRCFT) shows that the energy

eigenvalues (in oscillator units) of N harmonically trapped fermions can be

calculated from the scaling dimensions of N-fermion operators in the NRCFT.

They are also in one-to-one correspondence with zero-energy, scale-invariant

solutions to the N-body problem in free space. We show that these two mappings

of the trapped fermion problem to free space problems are related by an

automorphism of the SL(2,R) algebra of the conformal symmetry of fermions at

the unitary limit. This automorphism exchanges the internal Hamiltonian of the

gas with the trapping potential and hence provides a novel method for deriving

virial theorems for trapped Fermi gases at the unitary limit. We also show that

the state-operator correspondence can be applied directly in three spatial

dimensions by calculating the scaling dimensions of two- and three-fermion

operators and finding agreement with known exact results for energy levels of

two and three trapped fermions at the unitary limit.

\\ ( http://arxiv.org/abs/0712.0867 , 28kb)

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arXiv:0712.0880

Date: Thu, 6 Dec 2007 06:35:00 GMT (6kb)

Title: New Density Wave Insulating Phase of BEC in Optical Lattice

Authors: Manan Vyas, Priyam Das, and Prasanta K. Panigrahi

Categories: cond-mat.other

Comments: 3 pages

\\

A new density wave phase of Bose-Einstein condensate (BEC) is identified in

optical lattice, in the mean field approach. A dynamical phase transition is

found to take the BEC from superfluid to a known insulator phase at a certain

filling fraction, which separates another density wave type ground state from

the superfluid state. The latter two are connected by an irreversible phase

transition, however the superfluid and the density wave phases are mutually

exclusive. In contrast to the first one, which has a mono frequency character,

this new state necessarily possesses two frequency modulations over the

background, which are commensurate with the lattice.

\\ ( http://arxiv.org/abs/0712.0880 , 6kb)

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arXiv:0712.0951

Date: Thu, 6 Dec 2007 14:57:36 GMT (219kb)

Title: Tunneling of interacting fermions in 1D systems

Authors: Andrej Gendiar, Martin Mosko, Pavel Vagner and Radoslav Nemeth

Categories: cond-mat.mes-hall

Comments: Conference proceedings

Journal-ref: Acta Physica Polonica 108 (2005) 661-667

\\

Using the self-consistent Hartree-Fock approximation for spinless electrons

at zero temperature, we study tunneling of the interacting electron gas through

a single delta-barrier in a finite one-dimensional (1D) wire connected to

contacts. Our results exhibit features known from correlated many-body models.

In particular, the conductance decays with the wire length as $\propto

L^{-2\alpha}$, where the power $\alpha$ is universal. We also show that a

similar result for a wire conductance can be extracted from the persistent

current (I) through the delta-barrier in a 1D ring, where it is known that I

\propto L^{-1-\alpha}$.

\\ ( http://arxiv.org/abs/0712.0951 , 219kb)

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arXiv:0712.1002

Date: Thu, 6 Dec 2007 17:30:27 GMT (801kb)

Title: Phase Transitions in Finite Systems using Information Theory

Authors: P. Chomaz (GANIL), F. Gulminelli (LPCC)

Categories: cond-mat.stat-mech

Comments: To be published in AIP Conference Proceedings

Proxy: ccsd in2p3-00194045

Report-no: GANIL P 07 23

Journal-ref: Dans AIP Conference Proceedings - Dynamics and Thermodynamics of

Systems with Long Range Interactions: Theory and Experiments, Assisi (2007)

\\

(abridged) In this paper, we present the issues we consider as essential as

far as the statistical mechanics of finite systems is concerned. In particular,

we emphasis our present understanding of phase transitions in the framework of

information theory. Information theory provides a thermodynamically-consistent

treatment of finite, open, transient and expanding systems which are difficult

problems in approaches using standard statistical ensembles. As an example, we

analyze is the problem of boundary conditions, which in the framework of

information theory must also be treated statistically. We recall that out of

the thermodynamical limit the different ensembles are not equivalent and in

particular they may lead to dramatically different equation of states, in the

region of a first order phase transition. We recall the recent progresses

achieved in the understanding of first-order phase transition in finite

systems: the equivalence between the Yang-Lee theorem and the occurrence of

bimodalities in the intensive ensemble and the presence of inverted curvatures

of the thermodynamic potential of the associated extensive ensemble.

\\ ( http://arxiv.org/abs/0712.1002 , 801kb)

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arXiv:0712.1007

Date: Thu, 6 Dec 2007 17:38:40 GMT (57kb,D)

Title: Final-state effects in the radio frequency spectrum of strongly

interacting fermions

Authors: Sourish Basu, Erich J. Mueller

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

Comments: 4 pages, 2 figures

\\

We model the impact of final state interactions on the radio frequency

spectrum of a strongly interacting two-component superfluid Fermi gas. In

addition to a broad asymmetric peak coming from the break-up of Cooper pairs we

find that, for appropriate parameters, one can observe a sharp symmetric

"bound-bound" spectral line coming from the conversion of Cooper pairs in one

channels to pairs/molecules in another.

\\ ( http://arxiv.org/abs/0712.1007 , 57kb)

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arXiv:0712.0841

Date: Wed, 5 Dec 2007 22:29:01 GMT (869kb,D)

Title: Numerical Simulation of the Double Slit Interference with Ultracold

Atoms

Authors: Michel Gondran, Alexandre Gondran

Categories: quant-ph

Comments: 25 pages, 15 figures

Journal-ref: Am. J. Phys. 73, 2005

\\

We present a numerical simulation of the double slit interference experiment

realized by F. Shimizu, K. Shimizu and H. Takuma with ultracold atoms. We show

how the Feynman path integral method enables the calculation of the

time-dependent wave function. Because the evolution of the probability density

of the wave packet just after it exits the slits raises the issue of the

interpreting the wave/particle dualism, we also simulate trajectories in the de

Broglie-Bohm interpretation.

\\ ( http://arxiv.org/abs/0712.0841 , 869kb)

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\\

arXiv:0712.0990

Date: Thu, 6 Dec 2007 16:49:21 GMT (7kb,D)

Title: Off-Diagonal-Long-Range-Order Versus Entanglement

Authors: Dagomir Kaszlikowski and Marcin Wiesniak

Categories: quant-ph

Comments: 4 pages

\\

In this short note we discuss the relation between the so-called

Off-Diagonal-Long-Range-Order in many-body interacting quantum systems

introduced by C. N. Yang in Rev. Mod. Phys. {\bf 34}, 694 (1962) and

entanglement. We argue that there is a direct relation between these two

concepts.

\\ ( http://arxiv.org/abs/0712.0990 , 7kb)

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The replacements:

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arXiv:0706.2133

replaced with revised version Fri, 30 Nov 2007 11:36:34 GMT (78kb)

Title: Boson-Fermion pairing in Bose-Fermi mixtures on 1D optical lattices

Authors: X. Barillier-Pertuisel, S. Pittel, L.Pollet, P. Schuck

Categories: cond-mat.other nucl-th

Comments: accepted for publication by Phys. Rev. A

\\ ( http://arxiv.org/abs/0706.2133 , 78kb)

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\\

arXiv:0709.0012

replaced with revised version Fri, 30 Nov 2007 16:09:57 GMT (245kb)

Title: Observation of persistent flow of a Bose-Einstein condensate in a

toroidal trap

Authors: C. Ryu, M. F. Andersen, P. Clade, Vasant Natarajan, K. Helmerson, W.

D. Phillips

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

Comments: 1 file, 5 figures

\\ ( http://arxiv.org/abs/0709.0012 , 245kb)

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arXiv:0711.2141

replaced with revised version Mon, 3 Dec 2007 16:13:25 GMT (41kb)

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: 4 pages 3 figures revtex

\\ ( http://arxiv.org/abs/0711.2141 , 41kb)

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arXiv:0706.1821

replaced with revised version Sat, 1 Dec 2007 15:12:50 GMT (387kb)

Title: Holographic storage of multiple coherence gratings in a Bose-Einstein

condensate

Authors: Yutaka Yoshikawa, Kazuyuki Nakayama, Yoshio Torii, and Takahiro Kuga

Categories: physics.atom-ph

Comments: 5 pages, 4 figures

Journal-ref: Phys. Rev. Lett. 99, 220407 (2007)

\\ ( http://arxiv.org/abs/0706.1821 , 387kb)

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arXiv:0705.3768

replaced with revised version Tue, 4 Dec 2007 09:18:08 GMT (98kb)

Title: Bose-Einstein-condensed gases in arbitrarily strong random potentials

Authors: V.I.Yukalov, E.P.Yukalova, K.V.Krutitsky, R.Graham

Categories: cond-mat.dis-nn

Journal-ref: Phys. Rev. A 76, 053623 (2007)

DOI: 10.1103/PhysRevA.76.053623

\\ ( http://arxiv.org/abs/0705.3768 , 98kb)

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arXiv:0707.3140 (*cross-listing*)

replaced with revised version Wed, 5 Dec 2007 13:33:24 GMT (54kb)

Title: Interaction-controlled transport of an ultracold Fermi gas

Authors: Niels Strohmaier, Yosuke Takasu, Kenneth G\"unter, Robert J\"ordens,

Michael K\"ohl, Henning Moritz and Tilman Esslinger

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

Comments: 4 pages, 4 Postscript figures

Journal-ref: Phys. Rev. Lett. 99, 220601 (2007)

DOI: 10.1103/PhysRevLett.99.220601

\\ ( http://arxiv.org/abs/0707.3140 , 54kb)

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arXiv:0710.1549

replaced with revised version Thu, 6 Dec 2007 13:01:17 GMT (49kb)

Title: Phase separation in a polarized Fermi gas at zero temperature

Authors: S. Pilati and S. Giorgini

Categories: cond-mat.other

Comments: 4 pages, 4 figures, revised, accepted for publication in Phys. Rev.

Lett

\\ ( http://arxiv.org/abs/0710.1549 , 49kb)

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arXiv:0707.1653

replaced with revised version Thu, 6 Dec 2007 17:28:59 GMT (100kb)

Title: Chaos in kicked Bose-Einstein condensates: Bogoliubov resonances

Authors: J. Reslen, C.E. Creffield, and T.S. Monteiro

Categories: quant-ph

Comments: 5 pages

\\ ( http://arxiv.org/abs/0707.1653 , 100kb)

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\\

arXiv:0704.2627

replaced with revised version Thu, 6 Dec 2007 04:46:47 GMT (224kb)

Title: Atom-wave diffraction between the Raman-Nath and the Bragg regime:

Effective Rabi frequency, losses, and phase shifts

Authors: Holger Mueller, Sheng-wey Chiow, and Steven Chu

Categories: physics.atom-ph

Comments: Minor additions, more concise text. To appear in Phys. Rev. A. 20

pages, 10 figures

\\ ( http://arxiv.org/abs/0704.2627 , 224kb)

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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 Fri Dec 21 2007 - 07:56:10 EST

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