The following message was sent to the matts_arxiv list by Matthew Davis <mdavis_at_physics.uq.edu.au>
This week saw 26 new preprints and 11 replacements:
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arXiv:0808.4077
Date: Fri, 29 Aug 2008 11:37:05 GMT (112kb)
Title: Association of ultracold double-species bosonic molecules
Authors: C. Weber, G. Barontini, J. Catani, G. Thalhammer, M. Inguscio, and F.
Minardi
Categories: cond-mat.other
Comments: 5 pages, 4 figures
\\
We report on the creation of heterospecies bosonic molecules, associated from
an ultracold Bose-Bose mixture of 41K and 87Rb, by using a resonantly modulated
magnetic field close to two Feshbach resonances. We measure the binding energy
of the weakly bound molecular states versus the Feshbach field and compare our
results to theoretical predictions. We observe the broadening and asymmetry of
the association spectrum due to thermal distribution of the atoms, and a
frequency shift occurring when the binding energy depends nonlinearly on the
Feshbach field. A simple model is developed to quantitatively describe the
association process. Our work marks an important step forward in the
experimental route towards Bose-Einstein condensates of dipolar molecules.
\\ ( http://arxiv.org/abs/0808.4077 , 112kb)
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arXiv:0808.4137
Date: Fri, 29 Aug 2008 17:27:03 GMT (49kb)
Title: Effect of Induced Spin-Orbit Coupling for Atoms via Laser Fields
Authors: Xiong-Jun Liu, Mario F. Borunda, Xin Liu and Jairo Sinova
Categories: cond-mat.stat-mech cond-mat.mes-hall
Comments: 4 pages, 3 figures
\\
We propose an experimental scheme to study spin-orbit coupling effects in a
of two-dimensional (2D) Fermi atomic gas cloud by coupling its internal
electronic states (pseudospins) to radiation in a delta configuration. The
induced spin-orbit coupling can be of the Dresselhaus and Rashba type with and
without a Zeeman term. We show that the optically induced spin-orbit coupling
can lead to a spin-dependent effective mass under appropriate condition, with
one of them able to be tuned between positive and negative effective mass. As a
direct observable we show that in the expansion dynamics of the atomic cloud
the initial atomic cloud splits into two clouds for the positive effective mass
case regime, and into four clouds for the negative effective mass regime.
\\ ( http://arxiv.org/abs/0808.4137 , 49kb)
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arXiv:0808.4147
Date: Fri, 29 Aug 2008 18:29:33 GMT (731kb,D)
Title: Heteronuclear quantum gas mixtures
Authors: C. Ospelkaus, S. Ospelkaus
Categories: cond-mat.other cond-mat.stat-mech
Comments: 72 pages, accepted for publication in J. Phys. B: At. Mol. Opt. Phys.
as a PhD tutorial article
\\
This PhD tutorial article is a review of our experiments on heteronuclear
quantum gas mixtures at the University of Hamburg. We introduce basic
properties of trapped Fermi-Bose mixtures and demonstrate the achievement of
large quantum degenerate mixtures of 40K and 87Rb. Using heteronuclear Feshbach
resonances, we show how the heteronuclear interaction can be tuned, allowing us
to induce phase separation and collapse for large repulsive and attractive
interactions, respectively. We realize Fermi-Bose mixtures in 3D optical
lattices as a novel quantum many-body system and study coherence properties of
the mixture. Combining our experiments on lattices and Feshbach resonances, we
present the first realization of ultracold heteronuclear Feshbach molecules.
The molecules are created at individual sites of a 3D optical lattice. We
discuss lifetime, binding energy and rf association efficiency in terms of a
universal model and give an outlook for possible future developments.
\\ ( http://arxiv.org/abs/0808.4147 , 731kb)
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arXiv:0808.4143
Date: Fri, 29 Aug 2008 18:07:42 GMT (1976kb,D)
Title: Adiabaticity and localization in one-dimensional incommensurate lattices
Authors: E. E. Edwards, M. Beeler, Tao Hong, and S. L. Rolston
Categories: physics.atom-ph
Comments: 4 pages, 3 figures
\\
We experimentally investigate the role of adiabaticity on localization of a
Bose-Einstein condensate confined in a one-dimensional optical potential
comprised of a shallow primary lattice with additional one or two perturbing
lattice(s) of incommensurate period. We find that even a very weak perturbation
causes dramatic changes in the momentum distribution and makes adiabatic
loading of the combined lattice much more difficult than a single period
lattice. We interpret our results using a band structure model and the
one-dimensional Gross-Pitaevskii equation
\\ ( http://arxiv.org/abs/0808.4143 , 1976kb)
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arXiv:0808.4018 (*cross-listing*)
Date: Fri, 29 Aug 2008 03:56:42 GMT (272kb)
Title: Interference of the evolutions of Rb and Na Bose-Einstein condensates
Authors: Ma Luo, Chengguang Bao, Zhibing Li
Categories: physics.atm-clus physics.comp-ph
Comments: 9 pages, 4 figures
\\
Spin evolution of a mixture of two species of spin-1 Bose-Einstein
condensates (Rb and Na) has been investigated beyond the mean field theory.
Both analytical expression and numerical results on the populations of
spin-components are obtained. The interference is found to depend on the
initial states and the inter-species interaction sensitively. A number of
phenomena arising from the interference have been predicted. In particular,
periodic behavior and the alternate appearances of a zone of oscillation and a
long quiet zone are found.
\\ ( http://arxiv.org/abs/0808.4018 , 272kb)
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arXiv:0809.0038
Date: Sat, 30 Aug 2008 11:40:25 GMT (768kb)
Title: Path integral study of the role of correlation in exchange coupling of
spins in double quantum dots and optical lattices
Authors: Lei Zhang, Matthew Gilbert, Jesper Pedersen, and John Shumway
Categories: cond-mat.str-el
Comments: 5 pages, 6 figures
\\
We explore exchange coupling of a pair of spins in a double dot and in an
optical lattice. Our algorithm uses the frequency of exchanges in a bosonic
path integral, evaluated with Monte Carlo. This algorithm is simple enough to
be a "black box" calculator, yet gives insights into the role of correlation
through two-particle probability densities, visualization of instantons, and
pair correlation functions. We map the problem to Hubbard model and see that
exchange and correlation renormalize the effective parameters, dramatically
lowering U at larger separations.
\\ ( http://arxiv.org/abs/0809.0038 , 768kb)
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arXiv:0809.0040
Date: Sat, 30 Aug 2008 03:54:47 GMT (216kb)
Title: Phase Separation in two-Species Atomic Bose-Einstein Condensate with
Interspecies Feshbach Resonance
Authors: Lu Zhou, Jing Qian, Han Pu, Weiping Zhang, and Hong Y. Ling
Categories: cond-mat.mes-hall cond-mat.other
Comments: 8 pages, 3 figures
\\
We consider a mixture of two-species atomic Bose-Einstein codensates coupled
to a bound molecular state at zero temperature via interspecies Feshbach
resonance. The interspecies Feshbach coupling precludes the possibility of
doubly mixed phases while enables not only the pure molecular superfluid but
also the pure atomic superfluids to exist as distinct phases. We show that this
system is able to support a rich set of phase separations, including that
between two distinct mixed atom-molecule phases. We pay particular attention to
the effects of the Feschbach coupling and the particle collisions on the
miscibility of this multi-component condensate system.
\\ ( http://arxiv.org/abs/0809.0040 , 216kb)
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arXiv:0806.3191 (*cross-listing*)
Date: Thu, 19 Jun 2008 16:42:28 GMT (22kb)
Date (revised v2): Sat, 30 Aug 2008 17:03:32 GMT (22kb)
Title: Energy and Vorticity in Fast Rotating Bose-Einstein Condensates
Authors: M. Correggi, J. Yngvason
Categories: math-ph cond-mat.other math.MP
Comments: 19 pages, LaTeX; typos corrected, clarifying remarks added, some
rearrangements in the text
MSC-class: 35Q55,47J30,76M23
\\
We study a rapidly rotating Bose-Einstein condensate confined to a finite
trap in the framework of two-dimensional Gross-Pitaevskii theory in the strong
coupling (Thomas-Fermi) limit. Denoting the coupling parameter by $1/\eps^2$
and the rotational velocity by $\Omega$, we evaluate exactly the next to
leading order contribution to the ground state energy in the parameter regime
$|\log\eps|\ll \Omega\ll 1/(\eps^2|\log\eps|)$ with $\eps\to 0$. While the TF
energy includes only the contribution of the centrifugal forces the next order
corresponds to a lattice of vortices whose density is proportional to the
rotational velocity.
\\ ( http://arxiv.org/abs/0806.3191 , 22kb)
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arXiv:0809.0061
Date: Sat, 30 Aug 2008 14:02:51 GMT (213kb)
Title: Ultracold Molecules in the Ro-Vibrational Ground State
Authors: F. Lang, K. Winkler, C. Strauss, R. Grimm, J. Hecker Denschlag
Categories: quant-ph
Comments: 17 pages, 6 figures
\\
The successful production of quantum degenerate gases of weakly bound
molecules has triggered a quest for quantum gases of tightly bound molecules.
We report here on the first production of an ultracold gas of tightly bound
Rb_2 molecules in the ro-vibrational ground state, close to quantum degeneracy.
This was achieved by optically transferring weakly bound Rb2 molecules to the
absolute lowest level of the triplet ground state potential with a transfer
efficiency of about 90%. The transfer takes place in a 3D optical lattice which
traps a sizeable fraction of the tightly bound molecules with a lifetime
exceeding 200 ms. These results open the door for experiments with tightly
bound ultracold molecules, investigations of ultracold collisions and
chemistry, production of a molecular Bose-Einstein condensate (BEC), and
molecular quantum optics.
\\ ( http://arxiv.org/abs/0809.0061 , 213kb)
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arXiv:0809.0243
Date: Mon, 1 Sep 2008 13:36:02 GMT (233kb)
Title: Dispersion compensation in atom interferometry by a Sagnac phase
Authors: Marion Jacquey (LCAR), Alain Miffre (LCAR), G\'erard Tr\'enec (LCAR),
Matthias B\"uchner (LCAR), Jacques Vigu\'e (LCAR), Alexander Cronin
Categories: quant-ph
Journal-ref: Physical Review A: Atomic, Molecular and Optical Physics 78 (2008)
013638
DOI: 10.1103/PhysRevA.78.013638
\\
We reanalyzed our atom interferometer measurement of the electric
polarizability of lithium now accounting for the Sagnac effect due to Earth
rotation. The resulting correction to the polarizability is very small but the
visibility as a function of the applied phase shift is now better explained.
The fact that the Sagnac and polarizability phase shifts are both proportional
to $v^{-1}$, where $v$ is the atom velocity, suggests that a phase shift of the
Sagnac type could be used as a counterphase to compensate the electric
polarizability phase shift. This exact compensation opens the way to higher
accuracy measurements of atomic polarizabilities and we discuss how this can be
practically done and the final limitations of the proposed technique.
\\ ( http://arxiv.org/abs/0809.0243 , 233kb)
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arXiv:0809.0288
Date: Mon, 1 Sep 2008 18:08:03 GMT (913kb)
Title: Dynamic optical lattices: two-dimensional rotating and accordion
lattices for ultracold atoms
Authors: R. A. Williams, J. D. Pillet, S. Al-Assam, B. Fletcher, and C. J. Foot
Categories: quant-ph
Comments: 7 pages, 6 figures
\\
We demonstrate a novel experimental arrangement which rotates a 2D optical
lattice at frequencies up to several kilohertz. Ultracold atoms in such a
rotating lattice can be used for the direct quantum simulation of strongly
correlated systems under large effective magnetic fields, allowing
investigation of phenomena such as the fractional quantum Hall effect. Our
arrangement also allows the periodicity of a 2D optical lattice to be varied
dynamically, producing a 2D accordion lattice.
\\ ( http://arxiv.org/abs/0809.0288 , 913kb)
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arXiv:0809.0149
Date: Sun, 31 Aug 2008 20:23:56 GMT (412kb)
Title: Off-resonant Raman transitions impact in an atom interferometer
Authors: A. Gauguet (SYRTE), Tanja Mehlst\"aubler (SYRTE), Thomas L\'ev\`eque
(SYRTE), J. Le Gou\"et (SYRTE), Oualid Chaibi (SYRTE), B. Canuel (SYRTE),
Andre Clairon (SYRTE), Franck Pereira Dos Santos (SYRTE), Arnaud Landragin
(SYRTE)
Categories: physics.atom-ph
\\
We study the influence of off-resonant two photon transitions on high
precision measurements with atom interferometers based on stimulated Raman
transitions. These resonances induce a two photon light shift on the resonant
Raman condition. The impact of this effect is investigated in two highly
sensitive experiments: a gravimeter and a gyroscope-accelerometer. We show that
it can lead to significant systematic phase shifts, which have to be taken into
account in order to achieve best performances in term of accuracy and
stability.
\\ ( http://arxiv.org/abs/0809.0149 , 412kb)
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arXiv:0809.0312
Date: Mon, 1 Sep 2008 20:01:32 GMT (182kb)
Title: Probing spatial spin correlations of ultracold gases by quantum noise
spectroscopy
Authors: G. M. Bruun, Brian M. Andersen, Eugene Demler and Anders S.
S{\o}rensen
Categories: cond-mat.other
Comments: 4 pages, 3 figures
\\
Spin noise spectroscopy with a single laser beam is demonstrated
theoretically to provide a direct probe of the spatial correlations of cold
fermionic gases. We show how the generic many-body phenomena of anti-bunching,
pairing, antiferromagnetic, and algebraic spin liquid correlations can be
revealed in the measured spin noise as a function of laser width, temperature,
and frequency.
\\ ( http://arxiv.org/abs/0809.0312 , 182kb)
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arXiv:0809.0350
Date: Tue, 2 Sep 2008 05:37:24 GMT (871kb)
Title: Stability of superfluid Fermi gases in optical lattices
Authors: Yoshihiro Yunomae, Ippei Danshita, Daisuke Yamamoto, Nobuhiko Yokoshi,
and Shunji Tsuchiya
Categories: cond-mat.other
Comments: 4 pages, 4 figures, conference proceeding for ISQM-TOKYO'08
\\
Fermionic superfluid flow and its stability are theoretically investigated.
We consider the Fermi gases in moving one- and two-dimensional optical
lattices, and calculate the excitation spectrum on them. It is found that
low-lying excitations, called as Anderson-Bogoliubov (AB) mode, exhibit a
roton-like structure in a short-wavelength regime. Moreover, with increasing
lattice velocity, one of the roton-like minima reaches zero before the pair
breaking occurs. This means that the superfluid Fermi gases can be destabilized
due to the spontaneous emission of the roton-like AB mode instead of due to the
Cooper pair breaking.
\\ ( http://arxiv.org/abs/0809.0350 , 871kb)
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arXiv:0809.0440
Date: Tue, 2 Sep 2008 14:26:16 GMT (810kb,D)
Title: Transition from a Spin Luttinger-Liquid to a Bose-Einstein Condensate of
Magnons in the Quantum Spin Ladder (C5H12N)2CuBr4
Authors: B. Thielemann, Ch. R\"uegg, K. Kiefer, H.M. R{\o}nnow, P. Bouillot, C.
Kollath, E. Orignac, R. Citro, T. Giamarchi, A. M. L\"auchli, D. Biner, K.
Kr\"amer, F. Wolff-Fabris, V. Zapf, M. Jaime, J. Stahn, N.B. Christensen, B.
Grenier, D.F. McMorrow, J. Mesot
Categories: cond-mat.str-el
Comments: 4 pages, 4 figures
\\
The transition from a magnetic field-tuned spin Luttinger-liquid with
algebraic spin correlations to a Bose-Einstein Condensate of magnons with
long-range magnetic order is investigated in the two-leg spin ladder material
bis(piperidinium)tetrabromocuprate(II) (C5H12N)2CuBr4. By neutron diffraction
and measurements of the magnetocaloric effect we show that the ordering
temperature, transverse and longitudinal magnetizations, and critical behavior
are highly dominated by the tunable one-dimensional physics of the
weakly-coupled spin Luttinger-liquids. Our experimental results are in
excellent agreement with theoretical calculations with renormalized mean-field
interaction parameters.
\\ ( http://arxiv.org/abs/0809.0440 , 810kb)
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arXiv:0809.0449
Date: Tue, 2 Sep 2008 14:59:58 GMT (185kb)
Title: Point processes in arbitrary dimension from fermionic gases, random
matrix theory, and number theory
Authors: Salvatore Torquato, A. Scardicchio and Chase E Zachary
Categories: cond-mat.stat-mech
Comments: 40 pages, 11 figures, 1 table, iopart
\\
It is well known that one can map certain properties of random matrices,
fermionic gases, and zeros of the Riemann zeta function to a unique point
process on the real line. Here we analytically provide exact generalizations of
such a point process in d-dimensional Euclidean space for any d, which are
special cases of determinantal processes. In particular, we obtain the
n-particle correlation functions for any n, which completely specify the point
processes. We also demonstrate that spin-polarized fermionic systems have these
same n-particle correlation functions in each dimension. The point processes
for any d are shown to be hyperuniform. The latter result implies that the pair
correlation function tends to unity for large pair distances with a decay rate
that is controlled by the power law r^[-(d+1)]. We graphically display one- and
two-dimensional realizations of the point processes in order to vividly reveal
their "repulsive" nature. Indeed, we show that the point processes can be
characterized by an effective "hard-core" diameter that grows like the square
root of d. The nearest-neighbor distribution functions for these point
processes are also evaluated and rigorously bounded. Among other results, this
analysis reveals that the probability of finding a large spherical cavity of
radius r in dimension d behaves like a Poisson point process but in dimension
d+1 for large r and finite d. We also show that as d increases, the point
process behaves effectively like a sphere packing with a coverage fraction of
space that is no denser than 1/2^d.
\\ ( http://arxiv.org/abs/0809.0449 , 185kb)
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arXiv:0809.0340
Date: Tue, 2 Sep 2008 02:52:37 GMT (96kb)
Title: Radio frequency association of heteronuclear Feshbach molecules
Authors: C. Klempt, T. Henninger, O. Topic, M. Scherer, L.Kattner, W. Ertmer
and J. Arlt
Categories: quant-ph
Comments: 5 pages, 4 figures
\\
We present a detailed analysis of the production efficiency of weakly bound
heteronuclear KRb Feshbach molecules using radio frequency association in a
harmonic trap. The efficiency was measured in a wide range of temperatures,
binding energies and radio frequencies. A comprehensive analytical model is
shown to provide a detailed understanding of the observed asymmetric spectra
and a good quantitative agreement with the measured production rates. This
fully consistent model provides a deep understanding of the molecule
association process and paves the way for future experiments which rely on
Feshbach molecules e.g. for the production of deeply bound molecules.
\\ ( http://arxiv.org/abs/0809.0340 , 96kb)
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arXiv:0809.0399
Date: Tue, 2 Sep 2008 10:58:37 GMT (322kb)
Title: A vapor cell based on dispensers for laser spectroscopy
Authors: E. M. Bridge, J. Millen, C. S. Adams, M. P. A. Jones
Categories: physics.atom-ph physics.ins-det
Comments: 8 pages, 3 figures
\\
We describe a simple strontium vapor cell for laser spectroscopy experiments.
Strontium vapor is produced using an electrically heated commercial dispenser
source. The sealed cell operates at room temperature, and without a buffer gas
or vacuum pump. The cell was characterised using laser spectroscopy, and was
found to offer stable and robust operation, with an estimated lifetime of
>10,000 hours. By changing the dispenser, this technique can be readily
extended to other alkali and alkaline earth elements.
\\ ( http://arxiv.org/abs/0809.0399 , 322kb)
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arXiv:0809.0505
Date: Wed, 3 Sep 2008 08:17:46 GMT (276kb)
Title: Metastable superfluidity of repulsive fermionic atoms in optical
lattices
Authors: Achim Rosch, David Rasch, Benedikt Binz, Matthias Vojta
Categories: cond-mat.other cond-mat.supr-con
Comments: 4 pages, 3 figs
\\
Doubly occupied states of the fermionic Hubbard model have an exponentially
large lifetime in the limit of strong repulsive interactions U. We show that
this property can be used to prepare a metastable s-wave superfluid state for
fermionic atoms in optical lattices described by a large-U Hubbard model. When
an initial band-insulating state is expanded, the doubly occupied sites Bose
condense. A mapping to the ferromagnetic Heisenberg model in an external field
allows for a reliable solution of the problem. Nearest-neighbor repulsion is
important in stabilizing superfluidity.
\\ ( http://arxiv.org/abs/0809.0505 , 276kb)
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arXiv:0809.0586
Date: Wed, 3 Sep 2008 09:46:06 GMT (62kb)
Title: Reverse engineering in many-body quantum physics: What many-body system
corresponds to an effective single-particle equation?
Authors: J. P. Coe, K. Capelle, and I. D'Amico
Categories: cond-mat.other
Comments: 4 pages, 2 figures
\\
The mapping, exact or approximate, of a many-body problem onto an effective
single-body problem is one of the most widely used conceptual and computational
tools of physics. Here, we propose and investigate the inverse map of effective
approximate single-particle equations onto the corresponding many-particle
system. This approach allows us to understand which interacting system a given
single-particle approximation is actually describing, and how far this is from
the original physical many-body system. We illustrate the resulting reverse
engineering process by means of the Kohn-Sham equations of density-functional
theory. In this application, our procedure sheds light on the non-locality of
the density-potential mapping of DFT, and on the self-interaction error
inherent in approximate density functionals.
\\ ( http://arxiv.org/abs/0809.0586 , 62kb)
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arXiv:0809.0706
Date: Thu, 4 Sep 2008 13:33:30 GMT (831kb)
Title: Effective Action Approach for Quantum Phase Transitions in Bosonic
Lattices
Authors: Barry Bradlyn, Francisco Ednilson A. dos Santos, Axel Pelster
Categories: cond-mat.stat-mech
Comments: 30 pages, 7 figures
\\
Based on standard field-theoretic considerations, we develop an effective
action approach for investigating quantum phase transitions in lattice Bose
systems at arbitrary temperature. We begin by adding to the Hamiltonian of
interest a symmetry breaking source term. Using time-dependent perturbation
theory, we then expand the grand-canonical free energy as a double power series
in both the tunneling and the source term. From here, an order parameter field
is introduced in the standard way, and the underlying effective action is
derived via a Legendre transformation. Determining the Ginzburg-Landau
expansion to first order in the tunneling term, expressions for the Mott
insulator-superfluid phase boundary, condensate density, average particle
number, and compressibility are derived and analyzed in detail. Additionally,
excitation spectra in the ordered phase are found by considering both
longitudinal and transverse variations of the order parameter. Finally, these
results are applied to the concrete case of the Bose-Hubbard Hamiltonian on a
three dimensional cubic lattice, and compared with the corresponding results
from mean-field theory. Although both approaches yield the same Mott insulator
- superfluid phase boundary to first order in the tunneling, the predictions of
our effective action theory turn out to be superior to the mean-field results
deeper into the superfluid phase.
\\ ( http://arxiv.org/abs/0809.0706 , 831kb)
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arXiv:0809.0747
Date: Thu, 4 Sep 2008 04:43:28 GMT (17kb)
Title: Semiclassical theory of the trapped quasi-2D Bose gas
Authors: R.N. Bisset, D. Baillie and P.B. Blakie
Categories: cond-mat.other
Comments: 5 pages, 2 figures
\\
We develop a Hartree-Fock meanfield model for the harmonically trapped
quasi-2D Bose gas. This method is valid in the non-degenerate regime where
density fluctuations are approximately Gaussian. We compare our predictions to
a meanfield theory suggested by Holzmann et al., [Europhys. Lett., 82, 30001
(2008)], which involves a simplification of the meanfield interaction term. We
discuss the universal behavior of the Berezinskii-Kosterlitz-Thouless
transition for the uniform Bose gas and how this result should be extended to
the trapped case. Using our meanfield theory we are able to provide a
lower-bound for the transition temperature.
\\ ( http://arxiv.org/abs/0809.0747 , 17kb)
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arXiv:0809.0768
Date: Thu, 4 Sep 2008 08:27:15 GMT (1894kb)
Title: Coherent control of dressed matter waves
Authors: Alessandro Zenesini and Hans Lignier and Donatella Ciampini and Oliver
Morsch and Ennio Arimondo
Categories: cond-mat.other quant-ph
Comments: 5 pages, 4 figures
\\
By moving the pivot of a pendulum rapidly up and down one can create a stable
position with the pendulum's bob above the pivot rather than below it. This
surprising and counterintuitive phenomenon is a widespread feature of driven
systems and carries over into the quantum world. Even when the static
properties of a quantum system are known, its response to an explicitly
time-dependent variation of its parameters may be highly nontrivial, and
qualitatively new states can appear that were absent in the original system. In
quantum mechanics the archetype for this kind of behaviour is an atom in a
radiation field, which exhibits a number of fundamental phenomena such as the
modification of its g-factor in a radio-frequency field and the dipole force
acting on an atom moving in a spatially varying light field. These effects can
be successfully described in the so-called dressed atom picture. Here we show
that the concept of dressing can also be applied to macroscopic matter waves,
and that the quantum states of "dressed matter waves" can be coherently
controlled. In our experiments we use Bose-Einstein condensates in driven
optical lattices and demonstrate that the many-body state of this system can be
adiabatically and reversibly changed between a superfluid and a Mott insulating
state by varying the amplitude of the driving. Our setup represents a versatile
testing ground for driven quantum systems, and our results indicate the
direction towards new quantum control schemes for matter waves.
\\ ( http://arxiv.org/abs/0809.0768 , 1894kb)
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arXiv:0809.0771
Date: Thu, 4 Sep 2008 14:47:21 GMT (414kb)
Title: Visibility of Cold Atomic Gases in Optical Lattices for Finite
Temperatures
Authors: Alexander Hoffmann and Axel Pelster
Categories: cond-mat.stat-mech
Comments: Author Information under
http://www.theo-phys.uni-essen.de/tp/ags/pelster_dir/
\\
In nearly all experiments with ultracold atoms time-of-flight pictures are
the only data available. In this paper we present an analytical strong-coupling
calculation for those time-of-flight pictures of bosons in an optical lattice
in the Mott phase. This allows us to determine the visibility, which quantifies
the contrast of peaks in the time-of-flight pictures, and we suggest how to use
it as a thermometer.
\\ ( http://arxiv.org/abs/0809.0771 , 414kb)
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Just for interest's sake:
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arXiv:0809.0290
Date: Mon, 1 Sep 2008 18:25:14 GMT (37kb)
Title: What are scientific leaders? The introduction of a normalized impact
factor
Authors: George E. A. Matsas
Categories: physics.soc-ph physics.data-an
Comments: 2 pages and 2 figures
\\
We define a normalized impact factor suitable to assess in a simple way both
the strength of scientific communities and the research influence of
individuals. We define those ones with $NIF \geq 1$ as being scientific leaders
since they would influence their peers at least as much as they are influenced
by them. The NIF is distinguished because (a) this has a clear and universal
meaning being applicable with equal efficiency to individuals belonging to
scientific communities with quite different publication and citation traditions
and (b) this is robust against self-citation expedient. This is eventually
applied to a community derived from the list of outstanding referees recognized
by the American Physical Society in 2008.
\\ ( http://arxiv.org/abs/0809.0290 , 37kb)
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arXiv:0809.0522
Date: Tue, 2 Sep 2008 21:33:02 GMT (81kb)
Title: The first-mover advantage in scientific publication
Authors: M. E. J. Newman
Categories: physics.soc-ph
Comments: 7 pages, 3 figures
\\
Mathematical models of the scientific citation process predict a strong
"first-mover" effect under which the first papers in a field will, essentially
regardless of content, receive citations at a rate enormously higher than
papers published later. Moreover papers are expected to retain this advantage
in perpetuity -- they should receive more citations indefinitely, no matter how
many other papers are published after them. We test this conjecture against
data from a selection of fields and in several cases find a first-mover effect
of a magnitude similar to that predicted by the theory. Were we wearing our
cynical hat today, we might say that the scientist who wants to become famous
is better off -- by a wide margin -- writing a modest paper in next year's
hottest field than an outstanding paper in this year's. On the other hand,
there are some papers, albeit only a small fraction, that buck the trend and
attract significantly more citations than theory predicts despite having
relatively late publication dates. We suggest that papers of this kind, though
they often receive comparatively few citations overall, are probably worthy of
our attention.
\\ ( http://arxiv.org/abs/0809.0522 , 81kb)
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The replacements:
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arXiv:hep-th/0501058 (*cross-listing*)
replaced with revised version Fri, 29 Aug 2008 07:15:49 GMT (215kb)
Title: Entanglement Induced Fluctuations of Cold Bosons
Authors: Ram Brustein, Amos Yarom
Categories: hep-th cond-mat.other quant-ph
Comments: Replaced with published version. Added calculations, explanations and
clarifications, results unchanged
\\ ( http://arxiv.org/abs/hep-th/0501058 , 215kb)
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arXiv:0801.1743
replaced with revised version Fri, 29 Aug 2008 03:47:28 GMT (642kb)
Title: Temperature Effects in a Fermi Gas with Population Imbalance
Authors: Heron Caldas, and A. L. Mota
Categories: cond-mat.str-el cond-mat.supr-con hep-ph nucl-th
Comments: 9 pages, 12 figures; minor typos corrected, references added
Journal-ref: J. Stat. Mech. P08013 (2008)
\\ ( http://arxiv.org/abs/0801.1743 , 642kb)
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arXiv:0808.2652
replaced with revised version Thu, 28 Aug 2008 20:42:42 GMT (447kb)
Title: Squeezing Out the Entropy of Fermions in Optical Lattices
Authors: Tin-Lun Ho and Qi Zhou
Categories: cond-mat.other
Comments: 6 pages, 3 figures, misprints corrected
\\ ( http://arxiv.org/abs/0808.2652 , 447kb)
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arXiv:0712.2256
replaced with revised version Sun, 31 Aug 2008 19:36:40 GMT (257kb)
Title: Spin-orbit coupled Bose-Einstein condensates
Authors: Tudor Stanescu, Brandon Anderson and Victor Galitski
Categories: cond-mat.other cond-mat.stat-mech quant-ph
Comments: published version, 10 pages, 4 figures
Journal-ref: Phys. Rev. A 78, 023616 (2008)
DOI: 10.1103/PhysRevA.78.023616
\\ ( http://arxiv.org/abs/0712.2256 , 257kb)
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arXiv:0804.0109
replaced with revised version Sat, 30 Aug 2008 07:08:33 GMT (213kb)
Title: Mechanisms for Lasing with Cold Atoms as the Gain Medium
Authors: William Guerin (INLN), Franck Michaud (INLN), Robin Kaiser (INLN)
Categories: physics.atom-ph cond-mat.dis-nn physics.optics
Journal-ref: Physical Review Letters 101 (2008) 093002
DOI: 10.1103/PhysRevLett.101.093002
\\ ( http://arxiv.org/abs/0804.0109 , 213kb)
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arXiv:0712.2256
replaced with revised version Sun, 31 Aug 2008 19:36:40 GMT (257kb)
Title: Spin-orbit coupled Bose-Einstein condensates
Authors: Tudor Stanescu, Brandon Anderson and Victor Galitski
Categories: cond-mat.other cond-mat.stat-mech quant-ph
Comments: published version, 10 pages, 4 figures
Journal-ref: Phys. Rev. A 78, 023616 (2008)
DOI: 10.1103/PhysRevA.78.023616
\\ ( http://arxiv.org/abs/0712.2256 , 257kb)
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arXiv:0804.2272
replaced with revised version Wed, 3 Sep 2008 14:43:22 GMT (11kb)
Title: Quantum hydrodynamics and nonlinear differential equations for
degenerate Fermi gas
Authors: E. Bettelheim, A. G. Abanov, and P. Wiegmann
Categories: cond-mat.mes-hall cond-mat.str-el math-ph math.MP nlin.SI
Comments: 10+ pages, appendix with some technical details is added
Journal-ref: J. Phys. A: Math. Theor. 41 (2008) 392003
\\ ( http://arxiv.org/abs/0804.2272 , 11kb)
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arXiv:0806.3107
replaced with revised version Wed, 3 Sep 2008 04:14:54 GMT (512kb)
Title: The initial momentum dependence of the quantum resonance in the
delta-kicked rotor
Authors: J-A. Currivan, A. Ullah and M.D. Hoogerland
Categories: quant-ph
Comments: 7 pages, 5 figures
\\ ( http://arxiv.org/abs/0806.3107 , 512kb)
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arXiv:0711.2697
replaced with revised version Thu, 4 Sep 2008 18:54:41 GMT (177kb)
Title: Exact exponents of edge singularities in dynamic correlation functions
of 1D Bose gas
Authors: Adilet Imambekov and Leonid I. Glazman
Categories: cond-mat.str-el
Comments: minor misprints in published version fixed
Journal-ref: Phys. Rev. Lett. 100, 206805 (2008)
DOI: 10.1103/PhysRevLett.100.206805
\\ ( http://arxiv.org/abs/0711.2697 , 177kb)
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arXiv:0805.3047
replaced with revised version Thu, 4 Sep 2008 15:53:08 GMT (178kb)
Title: Critical Temperature Curve in the BEC-BCS Crossover
Authors: Evgeni Burovski, Evgeny Kozik, Nikolay Prokof'ev, Boris Svistunov,
Matthias Troyer
Categories: cond-mat.str-el cond-mat.supr-con
Comments: revtex, 4 pages, 3 figures, published version
Journal-ref: Phys. Rev. Lett. 101, 090402 (2008)
\\ ( http://arxiv.org/abs/0805.3047 , 178kb)
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arXiv:0808.2963
replaced with revised version Wed, 3 Sep 2008 21:21:27 GMT (567kb,D)
Title: A High Phase-Space-Density Gas of Polar Molecules
Authors: K.-K. Ni, S. Ospelkaus, M. H. G. de Miranda, A. Pe'er, B. Neyenhuis,
J. J. Zirbel, S. Kotochigova, P. S. Julienne, D. S. Jin, J. Ye
Categories: quant-ph cond-mat.other
Comments: 21 pages, 6 figures
\\ ( http://arxiv.org/abs/0808.2963 , 567kb)
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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 Sep 26 2008 - 08:47:50 EST
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