# Matt's arXiv selection: week ending 6 February 2009.

From: Matthew Davis <mdavis_at_physics.uq.edu.au>
Date: Fri, 1 May 2009 10:04:41 +1000

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

Dear subscribers,

There were 27 new preprints and 9 replacements for this week.

------------------------------------------------------------------------------
\\
arXiv:0901.4778
Date: Thu, 29 Jan 2009 21:01:54 GMT (342kb)

Title: Non-adiabaticity and nonlinearity of a many-particle Landau-Zener
Authors: A.P. Itin, P. T\"orm\"a
Categories: cond-mat.stat-mech
Comments: submitted to Phys. Rev. Lett
\\
We consider nonlinear dynamics of an interacting many-particle system with a
slowly changing parameter: a time-dependent Dicke model, which represents a
many-body generalization of the Landau-Zener model. Adiabaticity is destroyed
when a parameter crosses a critical value, even at very slow sweeping rates of
a parameter. Applying semiclassical analysis based on concepts of classical
adiabatic invariants, we derive a formula which accurately describes particle
distributions in the Hilbert space at wide range of parameters and initial
conditions of the system.
\\ ( http://arxiv.org/abs/0901.4778 , 342kb)
------------------------------------------------------------------------------
\\
arXiv:0901.4808
Date: Fri, 30 Jan 2009 00:23:27 GMT (691kb)

Title: Anomalous Spin segregation in a weakly interacting two-component Fermi
gas
Authors: Stefan S. Natu, Erich J. Mueller
Categories: cond-mat.other cond-mat.stat-mech
\\
We explain the spin segregation seen at Duke in a two-component gas of 6Li
[Du, Luo, Clancy and Thomas, Phys. Rev. Lett. 101,150401 (2008)] as a
mean-field effect describable via a collisionless Boltzmann equation. As seen
in experiments, we find that slight differences in the trapping potentials in
the two spin states drive small spin currents. Hartree-Fock type interactions
convert these currents into a redistribution of populations in energy space,
and consequently a long lived spin texture develops. We explore the interaction
strength dependence of these dynamics, finding close agreement with experiment.
\\ ( http://arxiv.org/abs/0901.4808 , 691kb)
------------------------------------------------------------------------------
\\
arXiv:0901.4951
Date: Fri, 30 Jan 2009 18:36:22 GMT (121kb)

Title: Perturbation theory for the Nonlinear Schroedinger Equation with a
random potential
Authors: Shmuel Fishman, Yevgeny Krivolapov and Avy Soffer
Categories: cond-mat.dis-nn
\\
A perturbation theory for the NLSE in 1D on a lattice was developed. The
small parameter is the strength of the nonlinearity. For this purpose secular
terms were removed and a probabilistic bound on small denominators was
developed. It was shown that the number of terms grows exponentially with the
order. The results of the perturbation theory are compared with numerical
calculations. An estimate on the remainder is obtained and it is demonstrated
that the series is asymptotic.
\\ ( http://arxiv.org/abs/0901.4951 , 121kb)
------------------------------------------------------------------------------
\\
arXiv:0901.4779
Date: Thu, 29 Jan 2009 21:31:58 GMT (186kb,D)

Title: Entangled Mechanical Oscillators
Authors: J. D. Jost, J. P. Home, J. M. Amini, D. Hanneke, R. Ozeri, C. Langer,
J. J. Bollinger, D. Leibfried, and D. J. Wineland
Categories: quant-ph
\\
Hallmarks of quantum mechanics include superposition and entanglement. In the
context of large complex systems, these features should lead to situations like
Schrodinger's cat, which exists in a superposition of alive and dead states
entangled with a radioactive nucleus. Such situations are not observed in
nature. This may simply be due to our inability to sufficiently isolate the
system of interest from the surrounding environment -- a technical limitation.
Another possibility is some as-of-yet undiscovered mechanism that prevents the
formation of macroscopic entangled states. Such a limitation might depend on
the number of elementary constituents in the system or on the types of degrees
of freedom that are entangled. One system ubiquitous to nature where
entanglement has not been previously demonstrated is distinct mechanical
oscillators. Here we demonstrate deterministic entanglement of separated
mechanical oscillators, consisting of the vibrational states of two pairs of
atomic ions held in different locations. We also demonstrate entanglement of
the internal states of an atomic ion with a distant mechanical oscillator.
\\ ( http://arxiv.org/abs/0901.4779 , 186kb)
------------------------------------------------------------------------------
\
arXiv:0901.4789
Date: Thu, 29 Jan 2009 21:51:28 GMT (243kb)

Title: Ultra-bright biphoton emission from an atomic vapor based on
Doppler-free four-wave-mixing and collective emission
Authors: Y. P. Huang and M. G. Moore
Categories: quant-ph
\\
We propose a novel butterfly' level scheme to generate highly correlated
photon pairs from atomic vapors. With multi-photon Doppler-free pumping,
background Rayleigh scattering is dipole-forbidden and collective emission is
permitted in all directions. This results in usable pairs generated
simultaneously in the full $4\pi$ solid angle. Collecting these pairs can
produce photon pairs at a rate of $\sim 10^{12}$ per second, given only
moderate ensemble sizes of $\sim 10^6$ atoms.
\\ ( http://arxiv.org/abs/0901.4789 , 243kb)
------------------------------------------------------------------------------
\\
arXiv:0901.4896
Date: Fri, 30 Jan 2009 14:46:27 GMT (744kb)

Title: Quantum phase diagram of fermion mixtures with population imbalance in
one-dimensional optical lattices
Authors: B. Wang, Han-Dong Chen, and S. Das Sarma
Categories: quant-ph
\\
With a recently developed time evolving block decimation (TEBD) algorithm, we
numerically study the ground state quantum phase diagram of fermi mixtures with
attractive inter-species interactions loaded in one-dimensional optical
lattices. For our study, we adopt a general asymmetric Hubbard model (AHM) with
species-dependent tunneling rates to incorporate the possibility of mass
imbalance in the mixtures. We find clear signatures for the existence of a
Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase in this model in the presence of
population imbalance. Our simulation also reveals that in the presence of mass
imbalance, the parameter space for FFLO states shrinks or even completely
vanishes depending on the strength of the attractive interaction and the degree
of mass imbalance.
\\ ( http://arxiv.org/abs/0901.4896 , 744kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0005
Date: Mon, 2 Feb 2009 17:01:06 GMT (101kb)

Title: Getting into Shape: Efficient Cooling Scheme for Fermionic Atoms in
Optical Lattices
Authors: Jean-Sebastien Bernier, Corinna Kollath, Antoine Georges, Lorenzo De
Leo, Fabrice Gerbier, Christophe Salomon, Michael K\"ohl
Categories: cond-mat.str-el
\\
We propose an experimental procedure to cool fermionic atoms loaded into an
optical lattice. The central idea is to spatially divide the system into
entropy-rich and -poor regions by shaping the confining potential profile.
Atoms in regions of high entropy per particle are subsequently isolated from
the system. We discuss how to experimentally carry out this proposal, and
perform a quantitative study of its efficiency. We find that the entropy per
particle, $s$, can typically be reduced by a factor of 10 such that entropies
lower than $s/k_B \sim 0.2$ can be reached. Cooling into highly sought-after
quantum phases (such as an antiferromagnet) can thus be achieved. We show that
this procedure is robust against variations of the experimental conditions.
\\ ( http://arxiv.org/abs/0902.0005 , 101kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0107
Date: Sun, 1 Feb 2009 06:19:39 GMT (369kb)

Title: One-Dimensional Anderson Localization in Certain Correlated Random
Potentials
Authors: Pierre Lugan (LCFIO), Alain Aspect (LCFIO), Laurent Sanchez-Palencia
(LCFIO), Dominique Delande (LKB - Jussieu), Beno\^it Gr\'emaud (LKB -
Jussieu, IPAL, CNRS), Cord A. M\"uller (LKB - Jussieu), Christian Miniatura
(IPAL, CNRS, INLN)
Categories: cond-mat.other
\\
We investigate Anderson localization in weak 1D speckle potentials. We show
that long-range correlations induce effective mobility edges corresponding to
sharp crossovers between regions here localization lengths differ by orders of
magnitude. Using perturbation theory, we derive analytical formulas up to two
orders beyond Born approximation which prove in excellent agreement with exact
numerical calculations. Finally, we analyze our findings in the light of a
diagrammatic approach.
\\ ( http://arxiv.org/abs/0902.0107 , 369kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0172
Date: Mon, 2 Feb 2009 00:26:57 GMT (111kb)

Title: Effects of a dilute gas of fermions on the superfluid-insulator phase
diagram of the Bose-Hubbard model
Authors: Sumanta Tewari, Roman Lutchyn, S. Das Sarma
Categories: cond-mat.str-el
Comments: 16 pages, 3 eps figures
\\
Building on the work of Fisher et al. (Phys. Rev. B 40, 546 (1989)), we
develop a framework for perturbation theory in the Bose-Hubbard model and apply
it to calculate the effects of a degenerate gas of spin-polarized fermions
interacting by contact interactions with the constituent bosons. For the
single-band Bose-Hubbard model, the only non-trivial effect of the fermions is
to induce an effective space- and time-dependent density-density interaction
among the bosons. Using a path integral formulation, we develop the appropriate
theory describing the perturbative effects of this fermion-mediated interaction
(fermionic screening) on the generic superfluid-insulator phase diagram. For
the single-band Bose-Hubbard model, we find that the net effect of the fermions
is to inherently suppress the Mott-insulating lobes and enhance the area
occupied by the superfluid phase in the phase diagram. For the more general
multi-band Bose-Hubbard model, we find that, in addition to the fermion
screening of the boson interactions, the virtual excitations of the bosons to
the higher Bloch bands coupled with the contact interactions with the fermions
result in an effective increase of the boson on-site repulsion. If this
renormalization of the boson on-site potential is dominant over the fermion
screening of the boson interactions, the area of the Mott insulating lobes of
the Bose-Hubbard phase diagram will be enhanced for either sign of the
boson-fermion interactions, as seen in recent experiments.
\\ ( http://arxiv.org/abs/0902.0172 , 111kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0327
Date: Mon, 2 Feb 2009 18:03:56 GMT (1548kb)

Title: Classical and quantum analysis of a heterotriatomic molecular
Bose-Einstein-condensate model
Authors: A. P. Tonel, C. C. N. Kuhn, G. Santos, A. Foerster, I. Roditi and Z.
V. T. Santos
Categories: cond-mat.other
Journal-ref: Phys. Rev. A 79, 013624 (2009) [9 pages]
DOI: 10.1103/PhysRevA.79.013624
\\
We investigate an integrable Hamiltonian modeling a heterotriatomic molecular
Bose-Einstein condensate. This model describes a mixture of two species of
atoms in different proportions, which can combine to form a triatomic molecule.
Beginning with a classical analysis, we determine the fixed points of the
system. Bifurcations of these points separate the parameter space into
different regions. Three distinct scenarios are found, varying with the atomic
population imbalance. This result suggests the ground-state properties of the
quantum model exhibit a sensitivity on the atomic population imbalance, which
is confirmed by a quantum analysis using different approaches, such as the
ground-state expectation values, the behavior of the quantum dynamics, the
energy gap, and the ground-state fidelity.
\\ ( http://arxiv.org/abs/0902.0327 , 1548kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0234
Date: Mon, 2 Feb 2009 10:06:08 GMT (846kb)

Title: Theory and experimental verification of Kapitza-Dirac-Talbot-Lau
interferometry
Authors: Klaus Hornberger, Stefan Gerlich, Hendrik Ulbricht, Lucia
Hackerm\"uller, Stefan Nimmrichter, Ilya V. Goldt, Olga Boltalina, Markus
Arndt
Categories: quant-ph
\\
Kapitza-Dirac-Talbot-Lau interferometry (KDTLI) has recently been established
for demonstrating the quantum wave nature of large molecules. A phase space
treatment permits us to derive closed equations for the near-field interference
pattern, as well as for the Moire-type pattern that would arise if the
molecules were to be treated as classical particles. The model provides a
simple and elegant way to account for the molecular phase shifts related to the
optical dipole potential as well as for the incoherent effect of photon
absorption at the second grating. We present experimental results for different
molecular masses, polarizabilities and absorption cross sections using
fullerenes and fluorofullerenes and discuss the alignment requirements. Our
results with C60 and C70, C60F36 and C60F48 verify the theoretical description
to a high degree of precision.
\\ ( http://arxiv.org/abs/0902.0234 , 846kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0109
Date: Mon, 2 Feb 2009 19:59:19 GMT (44kb)

Title: Suspension of atoms and gravimetry using a pulsed standing wave
Authors: K. J. Hughes, J. H. T. Burke, C. A. Sackett
Categories: physics.atom-ph
\\
Atoms from an otherwise unconfined 87Rb condensate are shown to be suspended
against gravity using repeated reflections from a pulsed optical standing wave.
Reflection efficiency was optimized using a triple-pulse sequence that,
theoretically, provides accuracies better than 99.9%. Experimentally, up to 100
reflections are observed, leading to dynamical suspension for over 100 ms. The
velocity sensitivity of the reflections can be used to determine the local
gravitational acceleration. Further, a gravitationally sensitive atom
interferometer was implemented using the suspended atoms, with packet coherence
maintained for a similar time. These techniques could be useful for the precise
measurement of gravity when it is impractical to allow atoms to fall freely
over a large distance.
\\ ( http://arxiv.org/abs/0902.0109 , 44kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0366
Date: Mon, 2 Feb 2009 21:00:06 GMT (25kb)

Title: Ground State Properties of Cold Bosonic Atoms At Large Scattering
Lengths
Authors: Jun Liang Song, Fei Zhou (UBC)
Categories: cond-mat.other
\\
In this letter, we study bosonic atoms at large scattering lengths using a
variational method where the condensation amplitude is a variational parameter.
We further examine momentum distribution functions, chemical potentials and
speed of sound, and spatial density profiles of cold bosonic atoms in a trap in
this limit. The later two properties turn out to bear similarities of those of
Fermi gases. Estimates obtained here are applicable near Feshbach resonances,
particularly when the fraction of atoms forming trimer structures is small and
can be tested in future cold atom experiments.
\\ ( http://arxiv.org/abs/0902.0366 , 25kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0388
Date: Mon, 2 Feb 2009 21:58:39 GMT (271kb)

Title: Dispersive spectrum and orbital order of spinless p-band fermions in an
optical lattice
Authors: Xiancong Lu and E. Arrigoni
Categories: cond-mat.str-el
\\
We study single-particle properties of a spinless p-band correlated fermionic
gas in an optical lattice by means of a variational cluster approach. The
single-particle spectral function is almost flat at half-filling and develops a
strongly dispersive behavior at lower fillings. The competition between
different orbital orderings is studied as a function of filling. We observe an
evolution between "antiferromagnetic" orbital order at and close to
half-filling to "ferromagnetic" orbital order at lower fillings. We discuss the
behavior of the momentum distribution for different values of the on-site
interaction. Finally, we introduce a new integration contour in the complex
plane which allows to efficiently carry out a sum over Matsubara frequencies.
\\ ( http://arxiv.org/abs/0902.0388 , 271kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0489
Date: Tue, 3 Feb 2009 14:50:25 GMT (187kb)

Title: ac-driven atomic quantum motor
Authors: A. V. Ponomarev, S. Denisov, P. Hanggi
Categories: physics.atom-ph cond-mat.other
\\
We invent an ac-driven quantum motor consisting of two different, interacting
ultracold atoms placed into a ring-shaped optical lattice and submerged in a
pulsating magnetic field. While the first atom carries a current, the second
one serves as a quantum starter. For fixed zero-momentum initial conditions the
asymptotic carrier velocity converges to a unique non-zero value. We also
demonstrate that this quantum motor performs work against a constant load.
\\ ( http://arxiv.org/abs/0902.0489 , 187kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0463
Date: Tue, 3 Feb 2009 09:59:39 GMT (243kb)

Title: Doppler-free spectroscopy of molecular iodine using a frequency-stable
light source at 578 nm
Authors: Feng-Lei Hong, Hajime Inaba, Kazumoto Hosaka, Masami Yasuda, and
Atsushi Onae
Categories: physics.atom-ph physics.optics
\\
A stable light source obtained using sum-frequency generation (SFG) is
developed for high-resolution spectroscopy at 578 nm. Hyperfine transitions of
molecular iodine are observed by using the SFG light source with saturation
spectroscopy. The light source is frequency stabilized to the observed
hyperfine transition and achieves a stability of 2*10-12 for a 1-s averaging
time. The absolute frequency of the light source stabilized on the a1 component
of the R(37)16-1 transition is determined as 518304551833 (2) kHz. This
transition serves as a frequency reference for the 1S0 - 3P0 optical clock
transition in neutral ytterbium (Yb).
\\ ( http://arxiv.org/abs/0902.0463 , 243kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0475
Date: Tue, 3 Feb 2009 11:00:26 GMT (2024kb)

Title: Radiofrequency multipole traps: Tools for spectroscopy and dynamics of
cold molecular ions
Authors: Roland Wester
Categories: physics.atom-ph
\\
Multipole radiofrequency ion traps are a highly versatile tool to study
molecular ions and their interactions in a well-controllable environment. In
particular the cryogenic 22-pole ion trap configuration is used to study
ion-molecule reactions and complex molecular spectroscopy at temperatures
between few Kelvin and room temperatures. This article presents a tutorial on
radiofrequency ion trapping in multipole electrode configurations. Stable
trapping conditions and buffer gas cooling, as well as important heating
mechanisms, are discussed. In addition, selected experimental studies on cation
and anion-molecule reactions and on spectroscopy of trapped ions are reviewed.
Starting from these studies an outlook on the future of multipole ion trap
research is given.
\\ ( http://arxiv.org/abs/0902.0475 , 2024kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0489
Date: Tue, 3 Feb 2009 14:50:25 GMT (187kb)

Title: ac-driven atomic quantum motor
Authors: A. V. Ponomarev, S. Denisov, P. Hanggi
Categories: physics.atom-ph cond-mat.other
\\
We invent an ac-driven quantum motor consisting of two different, interacting
ultracold atoms placed into a ring-shaped optical lattice and submerged in a
pulsating magnetic field. While the first atom carries a current, the second
one serves as a quantum starter. For fixed zero-momentum initial conditions the
asymptotic carrier velocity converges to a unique non-zero value. We also
demonstrate that this quantum motor performs work against a constant load.
\\ ( http://arxiv.org/abs/0902.0489 , 187kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0335 (*cross-listing*)
Date: Mon, 2 Feb 2009 18:47:32 GMT (237kb)

Title: Precision determination of electroweak coupling from atomic parity
violation and implications for particle physics
Authors: S. G. Porsev, K. Beloy, A. Derevianko
Categories: hep-ph physics.atom-ph
Comments: 4 pages/3 figs /1 table
\\
We carry out high-precision calculation of parity violation in cesium atom,
reducing theoretical uncertainty by a factor of two compared to previous
evaluations. We combine previous measurements with our calculations and extract
the weak charge of the 133Cs nucleus, Q_W = -73.16(29)_exp(20)_th. The result
is in agreement with the Standard Model (SM) of elementary particles. This is
the most accurate to-date test of the low-energy electroweak sector of the SM.
In combination with the results of high-energy collider experiments, we confirm
the energy-dependence (or "running") of the electroweak force over an energy
range spanning four orders of magnitude (from ~10 MeV to ~100 GeV).
Additionally, our result places constraints on a variety of new physics
scenarios beyond the SM. In particular, we increase the lower limit on the
masses of extra $Z$-bosons predicted by models of grand unification and string
theories.
\\ ( http://arxiv.org/abs/0902.0335 , 237kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0696
Date: Wed, 4 Feb 2009 10:53:56 GMT (172kb)

Title: Superfluid transition in a Bose gas with correlated disorder
Authors: S. Pilati, S. Giorgini and N. Prokof'ev
Categories: cond-mat.other
\\
The superfluid transition of a three-dimensional gas of hard-sphere bosons in
a disordered medium is studied using quantum Monte Carlo methods. Simulations
are performed in continuous space both in the canonical and in the
grand-canonical ensemble. At fixed density we calculate the shift of the
transition temperature as a function of the disorder strength, while at fixed
temperature we determine both the critical chemical potential and the critical
density separating normal and superfluid phases. In the regime of strong
disorder the normal phase extends up to large values of the degeneracy
parameter and the critical chemical potential exhibits a linear dependence in
the intensity of the random potential. The role of interactions and disorder
correlations is also discussed.
\\ ( http://arxiv.org/abs/0902.0696 , 172kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0739
Date: Wed, 4 Feb 2009 15:43:49 GMT (17kb,D)

Title: Biaxial nematic phases in ultracold dipolar Fermi gases
Authors: Benjamin M. Fregoso, Kai Sun, Eduardo Fradkin and Benjamin L. Lev
Categories: cond-mat.other
\\
Ultracold dipolar Fermi gases represent relatively unexplored, strongly
correlated systems arising from long-range and anisotropic interactions. We
demonstrate the possibility of a spontaneous symmetry breaking biaxial phase in
these systems, which may be realized in, e.g., gases of ultracold polar
molecules or strongly magnetic atoms. This biaxial nematic phase is manifest in
a spontaneous distortion of the Fermi surface perpendicular to the axis of
polarization. We describe these dipolar interaction induced phases using Landau
Fermi liquid theory.
\\ ( http://arxiv.org/abs/0902.0739 , 17kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0611
Date: Tue, 3 Feb 2009 21:01:00 GMT (573kb)

Title: Dissipation induced coherence and stochastic resonance of an open
two-mode Bose-Einstein condensate
Authors: D. Witthaut, F. Trimborn, and S. Wimberger
Categories: quant-ph
\\
We discuss the dynamics of a Bose-Einstein condensate in a double-well trap
subject to phase noise and particle loss. The phase coherence of a
weakly-interacting condensate, experimentally measured via the contrast in an
interference experiment, as well as the response to an external driving become
maximal for a finite value of the dissipation rate matching the intrinsic time
scales of the system. This can be understood as a stochastic resonance of the
many-particle system. Even stronger effects are observed when dissipation acts
in concurrence with strong inter-particle interactions, restoring the purity of
the condensate almost completely and increasing the phase coherence
significantly. Our theoretical results are backed by Monte Carlo simulations,
which show a good qualitative agreement and provide a microscopic explanation
for the observed stochastic resonance effect.
\\ ( http://arxiv.org/abs/0902.0611 , 573kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0670
Date: Wed, 4 Feb 2009 08:51:34 GMT (1026kb)

Title: Observation of continuous-wave squeezed light at 1550 nm
Authors: Moritz Mehmet, Sebastian Steinlechner, Tobias Eberle, Henning
Vahlbruch, Andr\'e Th\"uring, Karsten Danzmann, Roman Schnabel
Categories: quant-ph
\\
We report on the generation of continuous-wave squeezed vacuum states of
light at the telecommunication wavelength of 1550 nm. The squeezed vacuum
states were produced by type I optical parametric amplification (OPA) in a
standing-wave cavity built around a periodically poled potassium titanyl
phosphate (PPKTP) crystal. A non-classical noise reduction of 5.3 dB below the
shot noise was observed by means of balanced homodyne detection.
\\ ( http://arxiv.org/abs/0902.0670 , 1026kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0791
Date: Wed, 4 Feb 2009 20:56:57 GMT (389kb)

Title: Stable two-dimensional solitons in nonlinear lattices
Authors: Yaroslav V. Kartashov, Boris A. Malomed, Victor A. Vysloukh, Lluis
Torner
Categories: physics.optics
Comments: 12 pages, 3 figures, to appear in Optics Letters
\\
We address the existence and stability of two-dimensional solitons in optical
or matter-wave media, which are supported by purely nonlinear lattices in the
form of a periodic array of cylinders with self-focusing nonlinearity, embedded
into a linear material. We show that such lattices can stabilize
two-dimensional solitons against collapse. We also found that stable multipoles
and vortex solitons are also supported by the nonlinear lattices, provided that
the nonlinearity exhibits saturation.
\\ ( http://arxiv.org/abs/0902.0791 , 389kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0836
Date: Thu, 5 Feb 2009 03:42:43 GMT (567kb)

Title: Spectral function of spinless fermions on a one-dimensional lattice
Authors: Rodrigo G. Pereira, Steven R. White, Ian Affleck
Categories: cond-mat.str-el
\\
We study the spectral function of interacting one-dimensional fermions for an
integrable lattice model away from half-filling. The divergent power-law
singularity of the spectral function near the single-particle or single-hole
energy is described by an effective x-ray edge type model. At low densities and
for momentum near the zone boundary, we find a second divergent singularity at
higher energies which is associated with a two-particle bound state. We use the
Bethe ansatz solution of the model to calculate the exact singularity exponents
for any momentum and for arbitrary values of chemical potential and interaction
strength in the critical regime. We relate the singularities of the spectral
function to the long-time decay of the fermion Green's function and compare our
predictions with numerical results from the time-dependent density matrix
renormalization group (tDMRG). Our results show that the tDMRG method is able
to provide accurate time decay exponents in the cases of power-law decay of the
Green's function. Some implications for the line shape of the dynamical
structure factor away from half-filling are also discussed. In addition, the
spectral weight of the Luttinger liquid result for the dynamical structure
factor of the Heisenberg model at zero field is compared with the exact
two-spinon contribution.
\\ ( http://arxiv.org/abs/0902.0836 , 567kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0934
Date: Thu, 5 Feb 2009 16:09:18 GMT (2083kb)

Title: Interaction of dark-bright solitons in two-component Bose-Einstein
condensates
Authors: S. Rajendran, P. Muruganandam, M. Lakshmanan
Categories: cond-mat.other nlin.PS
\\
We study the interaction of dark-bright solitons in two component
Bose-Einstein condensates by suitably tailoring the trap potential, atomic
scattering length and atom gain or loss. We show that the coupled
Gross-Pitaevskii (GP) equation can be mapped onto the Manakov model. An
interesting class of matter wave solitons and their interaction are identified
with confining as well as expulsive trap potentials, which can be
experimentally realized in two component condensates.
\\ ( http://arxiv.org/abs/0902.0934 , 2083kb)
------------------------------------------------------------------------------
\\
arXiv:0902.0881
Date: Thu, 5 Feb 2009 11:01:05 GMT (103kb)

Title: Reversible state transfer between superconducting qubits and atomic
ensembles
Authors: D. Petrosyan, G. Bensky, G. Kurizki, I. Mazets, J. Majer, J.
Schmiedmayer
Categories: quant-ph
\\
We examine the possibility of coherent, reversible information transfer
between solid-state superconducting qubits and ensembles of ultra-cold atoms.
Strong coupling between these systems is mediated by a microwave transmission
line resonator that interacts near-resonantly with the atoms via their
optically excited Rydberg states. The solid-state qubits can then be used to
implement rapid quantum logic gates, while collective metastable states of the
atoms can be employed for long-term storage and optical read-out of quantum
information.
\\ ( http://arxiv.org/abs/0902.0881 , 103kb)
------------------------------------------------------------------------------

The replacements:

------------------------------------------------------------------------------
\\
arXiv:0810.5703
replaced with revised version Fri, 30 Jan 2009 08:19:19 GMT (2150kb)

Title: Stimulating the production of deeply bound RbCs molecules with laser
pulses: the role of spin-orbit coupling in forming ultracold molecules
Authors: Subhas Ghosal, Richard J. Doyle, Christiane P. Koch and Jeremy M.
Hutson
Categories: physics.atom-ph physics.chem-ph
\\ ( http://arxiv.org/abs/0810.5703 , 2150kb)
------------------------------------------------------------------------------
\\
arXiv:0807.2898
replaced with revised version Sun, 1 Feb 2009 01:06:25 GMT (166kb)

Title: Heavily Damped Motion of One-Dimensional Bose Gases in an Optical
Lattice
Authors: Ippei Danshita, Charles W. Clark
Categories: cond-mat.other
Comments: 4 pages, 5 figures, published version
Journal-ref: Phys. Rev. Lett. 102, 030407 (2009)
\\ ( http://arxiv.org/abs/0807.2898 , 166kb)
------------------------------------------------------------------------------
\\
arXiv:0807.4534
replaced with revised version Mon, 2 Feb 2009 11:54:45 GMT (55kb)

Title: Unconventional quantum phases of lattice bosonic mixtures
Authors: P. Buonsante, S. M. Giampaolo, F. Illuminati, V. Penna, A. Vezzani
Categories: cond-mat.other hep-lat physics.atom-ph quant-ph
Comments: 10 pages, 2 figures - to appear in the topical issue on "Novel
Quantum Phases and Mesoscopic Physics in Quantum Gases" of the European
Physical Journal B (2009)
\\ ( http://arxiv.org/abs/0807.4534 , 55kb)
------------------------------------------------------------------------------
\\
arXiv:0812.2701
replaced with revised version Sat, 31 Jan 2009 22:18:11 GMT (1221kb,D)

Title: Electro-Optical Nanotraps for Neutral Atoms
Authors: Brian Murphy and Lene Vestergaard Hau
Categories: physics.atom-ph cond-mat.mes-hall hep-ph physics.optics quant-ph
Comments: 5 pages, 3 figures. Fig. 1 appeared on the cover of the January 23,
2009 issue of PRL
Journal-ref: Phys. Rev. Lett. 102, 033003 (2009)
DOI: 10.1103/PhysRevLett.102.033003
\\ ( http://arxiv.org/abs/0812.2701 , 1221kb)
------------------------------------------------------------------------------
\\
arXiv:0811.3961
replaced with revised version Tue, 3 Feb 2009 10:30:20 GMT (1110kb,D)

Title: Practical scheme for a light-induced gauge field in an atomic Bose gas
Authors: Kenneth J. G\"unter, Marc Cheneau, Tarik Yefsah, Steffen P. Rath, and
Jean Dalibard
Categories: cond-mat.str-el cond-mat.mes-hall quant-ph
Journal-ref: Phys. Rev. A 79, 011604(R) (2009)
DOI: 10.1103/PhysRevA.79.011604
\\ ( http://arxiv.org/abs/0811.3961 , 1110kb)
------------------------------------------------------------------------------
\\
arXiv:0809.1539
replaced with revised version Wed, 4 Feb 2009 09:57:35 GMT (671kb)

Title: Pair correlations of a spin-imbalanced Fermi gas on two-leg ladders
Authors: A. E. Feiguin and F. Heidrich-Meisner
Categories: cond-mat.str-el cond-mat.supr-con
Comments: To appear in Phys. Rev. Lett.; minor revisions
\\ ( http://arxiv.org/abs/0809.1539 , 671kb)
------------------------------------------------------------------------------
\\
arXiv:0901.4631
replaced with revised version Wed, 4 Feb 2009 10:25:24 GMT (393kb)

Title: From Bogoliubov's approximation to Popov's hydrodynamic theory: a
unified picture of superfluidity
Authors: N. Dupuis
Categories: cond-mat.other
Comments: v2) 4 pages, 4 figures
\\ ( http://arxiv.org/abs/0901.4631 , 393kb)
-----------------------------------------------------------------------------
\\
arXiv:quant-ph/0701167
replaced with revised version Wed, 4 Feb 2009 12:27:37 GMT (636kb)

Title: Cold Atom Physics Using Ultra-Thin Optical Fibers: Light-Induced Dipole
Forces and Surface Interactions
Authors: G. Sagu\'e, E. Vetsch, W. Alt, D. Meschede and A. Rauschenbeutel
Categories: quant-ph
Journal-ref: PRL 99, 163602 (2007)
\\ ( http://arxiv.org/abs/quant-ph/0701167 , 636kb)
------------------------------------------------------------------------------
\\
arXiv:0808.3620
replaced with revised version Wed, 4 Feb 2009 15:00:04 GMT (1051kb)

Title: Observation of Cold Collisions between Trapped Ions and Trapped Atoms
Authors: Andrew T. Grier, Marko Cetina, Fedja Oru\v{c}evi\'c, Vladan Vuleti\'c
Categories: physics.atom-ph
Comments: 4 pages, 4 figures; Revision 1/V2: Revised in response to PRL
\\ ( http://arxiv.org/abs/0808.3620 , 1051kb)
------------------------------------------------------------------------------

Till next time,
Matt.

--
=========================================================================
Dr M. J. Davis,                      Associate Professor in Physics
School of Mathematics and Physics,   ph  : +61 7 334 69824
The University of Queensland,        fax : +61 7 336 51242
Brisbane, QLD 4072,                  mdavis_at_physics.uq.edu.au
Australia.                           www.physics.uq.edu.au/people/mdavis/
=========================================================================
Matt's arXiv selection: weekly summary of cold-atom papers from arXiv.org
http://www.physics.uq.edu.au/people/mdavis/matts_arXiv/
=========================================================================
Legal stuff: Unless stated otherwise, this e-mail represents only the
views of the sender and not the views of the University of Queensland
=========================================================================
`
Received on Fri May 01 2009 - 15:51:04 EST

This archive was generated by hypermail 2.2.0 : Fri May 29 2009 - 09:16:40 EST