# EARLY: Matt's arXiv selection for Thursday 13 July 2006.

From: Matthew Davis <mdavis_at_physics.uq.edu.au>
Date: Thu, 13 Jul 2006 18:00:56 +1000 (EST)

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

Hi all,

I'm getting on a plane bound for Innsbruck tomorrow, and so I decided to send
out an arXiv email today. The next one probably won't be until Monday 24th
July, or possibly even later.

The abstracts:

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Paper: cond-mat/0607179
Date: Fri, 7 Jul 2006 01:59:06 GMT (281kb)

Title: Visualization of vortex bound states in polarized Fermi gases at
unitarity
Authors: Hui Hu, Xia-Ji Liu, and Peter D. Drummond
Comments: 5pages, 4 figures, submitted to the AIP 17th National Congress (2006)
on June 12th
Subj-class: Superconductivity; Statistical Mechanics
\\
We analyse theoretically a single vortex in 3D trapped atomic Fermi gases
with population polarization near a broad Feshbach resonance. Above a critical
polarization the Andreev-like bound states inside the core become occupied for
the majority component. As a result, the local density difference at the core
center acquires a sudden rise at low temperautres. This provides a
visualization of the lowest bound state within the absorption imaging
technique. As the polarization increases, the core expands gradually, and
correspondingly, the energy of the lowest bound state decreases.
\\ ( http://arXiv.org/abs/cond-mat/0607179 , 281kb)
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Paper: cond-mat/0607184
Date: Fri, 7 Jul 2006 08:41:56 GMT (259kb)

Title: Broken axisymmetry phase of a spin-1 ferromagnetic Bose-Einstein
condensate
Authors: Keiji Murata, Hiroki Saito, and Masahito Ueda
Subj-class: Other
\\
A spin-1 ferromagnetic Bose-Einstein condensate subject to a certain magnetic
field exhibits a broken-axisymmetry phase in which the magnetization tilts
against the applied magnetic field due to the competition between
ferromagnetism and linear and quadratic Zeeman effects. The Bogoliubov analysis
shows that in this phase two Goldstone modes associated with U(1) and SO(2)
symmetry breakings exist, in which phonons and magnons are coupled to restore
the two broken symmetries.
\\ ( http://arXiv.org/abs/cond-mat/0607184 , 259kb)
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Paper: cond-mat/0607195
Date: Fri, 7 Jul 2006 14:24:45 GMT (98kb)

Title: Landau and dynamical instabilities of Bose-Einstein condensates with
superfluid flow in a Kronig-Penney potential
Authors: Ippei Danshita and Shunji Tsuchiya
Comments: 6 pages, 2 figures, Proceedings of the International Symposium on
Quantum Fluids and Solids (QFS2006)
Subj-class: Other
\\
We study the elementary excitations of Bose-Einstein condensates in a
one-dimensional periodic potential and discuss the stability of superfluid flow
based on the Kronig-Penney model. We analytically solve the Bogoliubov
equations and calculate the excitation spectrum. The Landau and dynamical
instabilities occur in the first condensate band when the superfluid velocity
exceeds certain critical values, which agrees with the result of condensates in
a sinusoidal potential. It is found that the onset of the Landau instability
coincides with the point where the perfect transmission of low-energy
excitations is forbidden, while the dynamical instability occurs when the
effective mass is negative. It is well known that the condensate band has a
peculiar structure called swallowtail when the periodic potential is shallow
compared to the mean field energy. We find that the upper side of the
swallowtail is dynamically unstable although the excitations have the linear
dispersion reflecting the positive effective mass.
\\ ( http://arXiv.org/abs/cond-mat/0607195 , 98kb)
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Paper: cond-mat/0607202
Date: Fri, 7 Jul 2006 16:45:58 GMT (45kb)

Title: Correlated Fermions on a Checkerboard Lattice
Authors: F. Pollmann, J. J. Betouras, K. Shtengel, P. Fulde
Subj-class: Strongly Correlated Electrons
\\
A model of strongly correlated spinless fermions hopping on a checkerboard
lattice is mapped onto a quantum fully-packed loop model. We identify the
number of fluctuationless states specific to the fermionic case. We also show
that for a class of fluctuating states, the fermionic sign problem can be
gauged away. This claim is supported by numerically evaluating the energies of
the low-lying states. Furthermore, we analyze in detail the excitations at the
Rokhsar-Kivelson point of this model thereby using the relation to the height
model and the single-mode approximation.
\\ ( http://arXiv.org/abs/cond-mat/0607202 , 35kb)
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Paper: quant-ph/0603229
replaced with revised version Fri, 7 Jul 2006 17:10:47 GMT (23kb)

Title: Spin Decoherence in Superconducting Atom Chips
Authors: Per Kristian Rekdal, Bo-Sture K. Skagerstam, Ulrich Hohenester, Asier
Eiguren
Comments: 4 pages, 2 figures. Physical Review Letters (in press)
Subj-class: Quantum Physics; Soft Condensed Matter
\\ ( http://arXiv.org/abs/quant-ph/0603229 , 23kb)
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Paper: quant-ph/0607048
Date: Thu, 6 Jul 2006 23:22:46 GMT (938kb)

Title: Nonlinear coherent dynamics of an atom in an optical lattice
Authors: V.Yu. Argonov and S.V. Prants
\\
We consider a simple model of lossless interaction between a two-level single
atom and a standing-wave single-mode laser field which creates a
one-dimensional optical lattice. Internal dynamics of the atom is governed by
the laser field which is treated to be classical with a large number of
photons. Center-of-mass classical atomic motion is governed by the optical
potential and the internal atomic degree of freedom. The resulting
Hamilton-Schr\"odinger equations of motion are a five-dimensional nonlinear
dynamical system with two integrals of motion. The main focus of the paper is
chaotic atomic motion that may be quantified strictly by positive values of the
maximal Lyapunov exponent. It is shown that atom, depending on the value of its
total energy, can either oscillate chaotically in a well of the optical
potential or fly ballistically with weak chaotic oscillations of its momentum
or wander in the optical lattice changing the direction of motion in a chaotic
way. In the regime of chaotic wandering atomic motion is shown to have fractal
properties. We find a useful tool to visualize complicated atomic motion --
Poincar\'e mapping of atomic trajectories in an effective three-dimensional
phase space onto planes of atomic internal variables and momentum. We find
common features with typical non-hyperbolic Hamiltonian systems -- chains of
resonant islands of different sizes embedded in a stochastic sea, stochastic
layers, bifurcations, and so on. The phenomenon of sticking of atomic
trajectories to boundaries of regular islands, that should have a great
influence to atomic transport in optical lattices, is found and demonstrated
numerically.
\\ ( http://arXiv.org/abs/quant-ph/0607048 , 938kb)
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Paper: physics/0607061
Date: Fri, 7 Jul 2006 02:33:34 GMT (218kb)

Title: Nonlinear magneto-optical rotation, Zeeman and hyperfine relaxation of
potassium atoms in a paraffin-coated cell
Authors: J. S. Guzman, A. Wojciechowski, J. E. Stalnaker, K. Tsigutkin, V. V.
Yashchuk, D. Budker
Subj-class: Atomic Physics
\\
Nonlinear magneto-optical Faraday rotation (NMOR) on the potassium D1 and D2
lines was used to study Zeeman relaxation rates in an antirelaxation
paraffin-coated 3-cm diameter potassium vapor cell. Intrinsic Zeeman relaxation
rates of $\gamma^{NMOR}/2\pi=2.0(6) {\rm Hz}$ were observed. The relatively
small hyperfine intervals in potassium lead to significant differences in NMOR
in potassium compared to rubidium and cesium. Using laser optical pumping,
widths and frequency shifts were also determined for transitions between
ground-state hyperfine sublevels of $^{39}$K atoms contained in the same
paraffin-coated cell. The intrinsic hyperfine relaxation rate of
$\gamma^{hf}_{expt}/2\pi = 10.6(7)$Hz and a shift of $-9.1(2)$Hz were
observed. These results show that adiabatic relaxation gives only a small
contribution to the overall hyperfine relaxation in the case of potassium, and
the relaxation is dominated by other mechanisms similar to those observed in
previous studies with rubidium.
\\ ( http://arXiv.org/abs/physics/0607061 , 218kb)
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Paper: cond-mat/0607228
Date: Mon, 10 Jul 2006 03:26:37 GMT (628kb)

Title: Degenarate Fermi Gases of Ytterbium
Authors: Takeshi Fukuhara, Yosuke Takasu, Mitsutaka Kumakura, and Yoshiro
Takahashi
Subj-class: Other
\\
An evaporative cooling was performed to cool the fermionic $^{173}$Yb atoms
in a crossed optical dipole trap. The elastic collision rate, which is
important for the evaporation, turns out to be large enough from our study.
This large collision rate leads to efficient evaporation and we have
successfully cooled the atoms below 0.6 of the Fermi temperature, that is to
say, to a quantum degenerate regime. In this regime, a plunge of evaporation
efficiency is observed as the result of the Fermi degeneracy.
\\ ( http://arXiv.org/abs/cond-mat/0607228 , 628kb)
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Paper: cond-mat/0607235
Date: Mon, 10 Jul 2006 13:23:10 GMT (67kb)

Title: Quench dynamics and non equilibrium phase diagram of the Bose-Hubbard
model
Authors: Corinna Kollath, Andreas Laeuchli, and Ehud Altman
Subj-class: Other
\\
We investigate the time evolution of correlations in the Bose-Hubbard model
following a quench from the superfluid to the Mott insulating phase. For large
values of the final interaction strength the system approaches a distinctly
non-equilibrium steady state that bares strong memory of the initial
conditions. In contrast, when the final interaction strength is comparable to
the hopping, the correlations are rather well approximated by those at thermal
equilibrium. The existence of two distinct non-equilibrium regimes is
surprising given the non-integrability of the Bose-Hubbard model. We relate
this phenomena to the role of quasi-particle interactions in the Mott
insulating state.
\\ ( http://arXiv.org/abs/cond-mat/0607235 , 67kb)
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Paper: cond-mat/0607236
Date: Mon, 10 Jul 2006 13:24:49 GMT (807kb)

Title: Stability and properties of striped phases in systems of interacting
fermions or hard-core bosons
Authors: Volodymyr Derzhko
Comments: PhD thesis, 100 pages, 37 figures, 33 tables
Subj-class: Strongly Correlated Electrons; Statistical Mechanics
\\
In this thesis we deal with the specific collective phenomena in condensed
matter - striped-structures formation. Such structures are observed in
different branches of condensed matter physics, like surface physics or physics
of high-temperature superconductors. These quasi-one-dimensional objects appear
in theoretical analyses as well as in computer simulations of different
theoretical models. Here, the main topic of interest is the stability of
striped structures in certain quantum models, where a tendency towards
crystallization competes with a tendency towards phase separation, and some
basic properties of these structures.
\\ ( http://arXiv.org/abs/cond-mat/0607236 , 807kb)
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Paper: cond-mat/0607246
Date: Mon, 10 Jul 2006 17:14:17 GMT (132kb)

Title: Metal-Insulator Transition Revisited for Cold Atoms in Non-Abelian Gauge
Potentials
Authors: Indubala I. Satija, Daniel C. Dakin and Charles W. Clark
Comments: 4 pages, 4 figures, see http://physics.gmu.edu/~isatija/recentpub.htm
for high resolution figures
Subj-class: Other
\\
We discuss the possibility of realizing metal-insulator transitions with
ultracold atoms in two-dimensional optical lattices in the presence of
artificial gauge potentials. Such transitions have been extensively studied for
magnetic fields corresponding to Abelian gauges; they occur when the magnetic
flux penetrating the lattice plaquette is an irrational multiple of the
magnetic flux quantum. Here we present the first study of these transitions for
non-Abelian U(2) gauge fields, which can be realized with atoms with two pairs
of degenerate internal states. In contrast to the Abelian case, the spectrum
and localization transition in the non-Abelian case is strongly influenced by
atomic momenta. In addition to determining the localization boundary, the
momentum fragments the spectrum and the minimum energy viewed as a function of
momentum exhibits a step structure. Other key characteristics of the
non-Abelian case include the absence of localization for certain states and
satellite fringes around the Bragg peaks in the momentum distribution and an
interesting possibility that the transition can be tuned by the atomic momenta.
\\ ( http://arXiv.org/abs/cond-mat/0607246 , 132kb)
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Paper: cond-mat/0607251
Date: Mon, 10 Jul 2006 19:43:33 GMT (49kb)

Title: Quantum Phase Transitions of Hard-Core Bosons in Background Potentials
Authors: Anand Priyadarshee, Shailesh Chandrasekharan, Ji-Woo Lee, and Harold
U. Baranger
Subj-class: Statistical Mechanics; Superconductivity
\\
We study the zero temperature phase diagram of hard core bosons in two
dimensions subjected to three types of background potentials: staggered,
uniform, and random. In all three cases there is a quantum phase transition
from a superfluid (at small potential) to a normal phase (at large potential),
but with different universality classes. As expected, the staggered case
belongs to the XY universality, while the uniform potential induces a mean
field transition. The disorder driven transition is clearly different from
both; in particular, we find z~1.4, \nu~1, and \beta~0.6.
\\ ( http://arXiv.org/abs/cond-mat/0607251 , 49kb)
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Paper: cond-mat/0602274
replaced with revised version Mon, 10 Jul 2006 18:55:07 GMT (26kb)

Title: Induced P-wave Superfluidity in Asymmetric Fermi Gases
Authors: Aurel Bulgac, Michael McNeil Forbes, Achim Schwenk
Subj-class: Other; Superconductivity
Journal-ref: Phys. Rev. Lett. 97, 020402 (2006)
DOI: 10.1103/PhysRevLett.97.020402
\\ ( http://arXiv.org/abs/cond-mat/0602274 , 26kb)
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Paper: quant-ph/0607064
Date: Mon, 10 Jul 2006 18:46:31 GMT (991kb)

Title: Manipulation of matter waves using Bloch and Bloch-Zener oscillations
Authors: B. M. Breid, D. Witthaut and H. J. Korsch
\\
We present theoretical and numerical results on the dynamics of ultracold
atoms in an accelerated single- and double-periodic optical lattice. In the
single-periodic potential Bloch oscillations can be used to generate fast
directed transport with very little dispersion. The dynamics in the
double-periodic system is dominated by Bloch-Zener oscillations, i.e. the
interplay of Bloch oscillations and Zener tunneling between the subbands. Apart
from directed transport, the latter system permits various interesting
applications, such as widely tunable matter wave beam splitters and
Mach-Zehnder interferometry. As an application, a method for efficient probing
of small nonlinear mean-field interactions is suggested.
\\ ( http://arXiv.org/abs/quant-ph/0607064 , 991kb)
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Paper: physics/0607075
Date: Sun, 9 Jul 2006 21:11:42 GMT (132kb)

Title: Rogue decoherence in the formation of a macroscopic atom-molecule
superposition
Authors: Olavi Dannenberg and Matt Mackie
Comments: 10 pages, 4 figures, 46+ references; submitted to PRA
Subj-class: Atomic Physics; Chemical Physics
\\
We theoretically examine two-color photoassociation of a Bose-Einstein
condensate, focusing on the role of rogue decoherence in the formation of
macroscopic atom-molecule superpositions. Rogue dissociation occurs when two
zero-momentum condensate atoms are photoassociated into a molecule, which then
dissociates into a pair of atoms of equal-and-opposite momentum, instead of
dissociating back to the zero-momentum condensate. As a source of decoherence
that may damp quantum correlations in the condensates, rogue dissociation is an
obstacle to the formation of a macroscopic atom-molecule superposition. We
study rogue decoherence in a setup which, without decoherence, yields a
macroscopic atom-molecule superposition, and find that the most favorable
conditions for said superposition are a density ~ 1e12 atoms per cc and
temperature ~ 1e-10.
\\ ( http://arXiv.org/abs/physics/0607075 , 132kb)
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Paper: physics/0607084
Date: Mon, 10 Jul 2006 18:13:21 GMT (36kb)

Title: Ultracold Rb-OH collisions and prospects for sympathetic cooling
Authors: M. Lara, J. L. Bohn, D. Potter, P. Soldan, and J. Hutson
Subj-class: Atomic Physics
\\
We have computed ab inito cross sections for cold collisions of Rb atoms with
OH radicals. We predict collision rate constants of order 10^{-11} cm^3/s at
temperatures in the range 10-100 mK at which molecules have already been
produced experimentally. However, we also find that in these collisions the
molecules have a strong propensity for changing their internal state, which
could make sympathetic cooling of OH in a Rb buffer gas problematic in
magnetostatic or electrostatic traps.
\\ ( http://arXiv.org/abs/physics/0607084 , 36kb)
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Paper: cond-mat/0607253
Date: Mon, 10 Jul 2006 20:08:02 GMT (45kb)

Title: Classifying Novel Phases of Spinor Atoms
Authors: Ryan Barnett, Ari Turner, Eugene Demler
Subj-class: Strongly Correlated Electrons
\\
We consider many-body states of bosonic spinor atoms which, at the mean-field
level, can be characterized by a single-particle wave function. Such states
include BEC phases and insulating Mott states with one atom per site. We
describe and apply a classification scheme that makes explicit spin symmetries
of such states and enables one to naturally analyze their collective modes and
topological excitations. Quite generally, the method allows classification of a
spin F system as a polyhedron with 2F vertices. After discussing the general
formalism we apply it to the many-body states of bosons with hyperfine spins
two and three. For spin-two atoms we find the ferromagnetic state, a continuum
of nematic states, and a state having the symmetry of the point group of the
regular tetrahedron. For spin-three atoms we obtain similar ferromagnetic and
nematic phases as well as states having symmetries of various types of
polyhedra with six vertices: the hexagon, the pyramid with pentagonal base, the
prism, and the octahedron.
\\ ( http://arXiv.org/abs/cond-mat/0607253 , 45kb)
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Paper: cond-mat/0607274
Date: Tue, 11 Jul 2006 14:18:04 GMT (283kb)

Title: Persistent current of atoms in a ring optical lattice
Authors: Andrey R. Kolovsky
Subj-class: Soft Condensed Matter; Mesoscopic Systems and Quantum Hall Effect
\\
We consider a small ensemble of Bose atoms in a ring optical lattice with
weak disorder. The atoms are assumed to be initially prepared in a superfluid
state with non-zero quasimomentum and, hence, may carry matter current. It is
found that the atomic current persists in time for a low value of the
quasimomentum but decays exponentially for a high (around one quater of the
Brillouin zone) quasimomentum. The explanation is given in terms of low- and
high-energy spectra of the Bose-Hubbard model, which we describe using the
Bogoliubov and random matrix theories, respectively.
\\ ( http://arXiv.org/abs/cond-mat/0607274 , 283kb)
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Paper (*cross-listing*): nlin.PS/0607009
Date: Fri, 7 Jul 2006 21:39:20 GMT (456kb)

Title: Modulated Amplitude Waves in Collisionally Inhomogeneous Bose-Einstein
Condensates
Authors: Mason A. Porter, P. G. Kevrekidis, Boris A. Malomed, and D. J.
Frantzeskakis
Comments: 24 pages, 10 figures (many with several parts), submitted to Physica
D; higher resolution versions of some figures are available at
http://www.its.caltech.edu/~mason/papers
Subj-class: Pattern Formation and Solitons; Other; Atomic Physics; Dynamical
Systems
\\
We investigate the dynamics of an effectively one-dimensional Bose-Einstein
condensate (BEC) with the scattering length $a$ subjected to a spatially
periodic modulation, $a=a(x) = a(x + L)$. This "collisionally inhomogeneous"
BEC is described by a Gross-Pitaevskii (GP) equation with a nonlinearity
coefficient that is a periodic function of $x$. We transform this GP equation
into a constant-nonlinearity GP equation with an effective potential and study
a class of the latter's extended wave solutions. For small inhomogeneities, the
effective potential takes a form reminiscent of a superlattice, and the
amplitude dynamics of the BEC's coherent structures are described by a
nonlinear generalized Ince equation. In the small-amplitude limit, we use
averaging to construct modulated amplitude wave (MAW) solutions, whose
stability we subsequently examine using both numerical simulations of the
original GP equation and fixed point computations with the MAWs as numerically
exact solutions. We show that "on-site" solutions, whose maxima correspond to
maxima of the "nonlinear lattice" $a(x)$, are significantly more stable than
"off-site" solutions.
\\ ( http://arXiv.org/abs/nlin/0607009 , 456kb)
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Paper: cond-mat/0508645
replaced with revised version Tue, 11 Jul 2006 15:32:34 GMT (33kb)

Title: Potential-energy (BCS) to kinetic-energy (BEC)-driven pairing in the
attractive Hubbard model
Authors: B. Kyung, A. Georges, and A. -M. S. Tremblay
Subj-class: Strongly Correlated Electrons; Superconductivity
Journal-ref: Phys. Rev. B 74, 024501 (2006)
\\ ( http://arXiv.org/abs/cond-mat/0508645 , 33kb)
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Paper: cond-mat/0511647
replaced with revised version Tue, 11 Jul 2006 08:13:14 GMT (21kb)

Title: Thermodynamic properties of a trapped Bose gas : A diffusion Monte Carlo
study
Authors: S Datta
Subj-class: Statistical Mechanics
\\ ( http://arXiv.org/abs/cond-mat/0511647 , 21kb)
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Paper: cond-mat/0604580
replaced with revised version Tue, 11 Jul 2006 16:04:49 GMT (16kb)

Title: Superfluidity in a Three-flavor Fermi Gas with SU(3) Symmetry
Authors: Lianyi He, Meng Jin and Pengfei Zhuang
Comments: 9 pages, 2 figures, title slightly changed
Subj-class: Other; Superconductivity; Atomic Physics
\\ ( http://arXiv.org/abs/cond-mat/0604580 , 16kb)
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Paper: cond-mat/0607294
Date: Tue, 11 Jul 2006 20:17:57 GMT (513kb)

Title: Strongly correlated 2D quantum phases with cold polar molecules:
controlling the shape of the interaction potential
Authors: H.P. B\"uchler, E. Demler, M. Lukin, A. Micheli, N. Prokof'ev, G.
Pupillo, and P. Zoller
Subj-class: Statistical Mechanics
\\
We discuss techniques to tune and shape the long-range part of the
interaction potentials in quantum gases of polar molecules by dressing
rotational excitations with static and microwave fields. This provides a novel
tool towards engineering strongly correlated quantum phases in combination with
low dimensional trapping geometries. As an illustration, we discuss a 2D
crystalline phase, and a superfluid-crystal quantum phase transition.
\\ ( http://arXiv.org/abs/cond-mat/0607294 , 513kb)
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Paper: cond-mat/0607297
Date: Tue, 11 Jul 2006 23:57:26 GMT (138kb)

Title: Melting of Discrete Vortices via Quantum Fluctuations
Authors: Chaohong Lee, Tristram J. Alexander, and Yuri S. Kivshar
Subj-class: Other
\\
We consider nonlinear boson states with a nontrivial phase structure in the
three-site Bose-Hubbard ring, {\em quantum discrete vortices} (or {\em
q-vortices}), and study their "melting" under the action of quantum
fluctuations. We calculate the spatial correlations in the ground states to
show the superfluid-insulator crossover and analyze the fidelity between the
exact and variational ground states to explore the validity of the classical
analysis. We examine the phase coherence and the effect of quantum fluctuations
on q-vortices and reveal that the breakdown of these coherent structures
through quantum fluctuations accompanies the superfluid-insulator crossover.
\\ ( http://arXiv.org/abs/cond-mat/0607297 , 138kb)
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Paper: cond-mat/0607298
Date: Wed, 12 Jul 2006 01:36:27 GMT (690kb)

Title: Superfluid Expansion of a Strongly Interacting Fermi Gas
Authors: C.H. Schunck, M.W. Zwierlein, A. Schirotzek, and W. Ketterle
Subj-class: Superconductivity; Strongly Correlated Electrons
\\
We study the expansion of a rotating, superfluid Fermi gas. The presence and
absence of vortices in the rotating gas is used to distinguish superfluid and
normal parts of the expanding cloud. We find that the superfluid pairs survive
during the expansion until the density decreases below a critical value. Our
observation of superfluid flow at this point extends the range where fermionic
superfluidity has been studied to densities of 1.2 10^{11} cm^{-3}, about an
order of magnitude lower than any previous study.
\\ ( http://arXiv.org/abs/cond-mat/0607298 , 690kb)
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Paper: cond-mat/0607123
replaced with revised version Wed, 12 Jul 2006 16:05:39 GMT (565kb)

Title: Adiabatic Phase Diagram on Degenerate Fermi Gas with Feshbach-Resonance
Authors: S. Watabe, T. Nikuni, N. Nygaard, J. E. Williams, C. W. Clark
Comments: 6 pages, 7 figures, submitted to Quantum Fluids and Solids Conference
(QFS 2006)
Subj-class: Other
\\ ( http://arXiv.org/abs/cond-mat/0607123 , 565kb)
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Paper: physics/0607120
Date: Wed, 12 Jul 2006 17:09:32 GMT (293kb)

Title: Suppression of reflection from the grid boundary in solving the
time-dependent Schroedinger equation by split-step technique with fast
Fourier transform
Authors: A. A. Gonoskov and I. A. Gonoskov
Subj-class: Atomic Physics; Optics
\\
We present an approach to numerically solving the time-dependent Schroedinger
equation and other parabolic equations by the split-step technique with fast
Fourier transform, which suppresses the backreflection of waves from the grid
boundaries with any specified accuracy. Most importantly, all known methods
work well only for a narrow region of incident waves spectrum, and the proposed
method provides absorption of any wave whose length is large enough in
comparison with the size of absorption region.
\\ ( http://arXiv.org/abs/physics/0607120 , 293kb)
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Paper: cond-mat/0607277
Date: Tue, 11 Jul 2006 15:02:52 GMT (118kb)

Title: Rabi Lattices
Authors: Y. D. Chong, David E. Pritchard and Marin Soljacic
Subj-class: Other; Optics
\\
We present a microscopic model of two-level atoms localized in a lattice,
based on the Hopfield theory of exciton polaritons. In addition to a
polaritonic gap at the exciton energy, a photonic band gap opens up at the
Brillouin zone boundary. Upon tuning the lattice period to match the photonic
gap with the exciton energy, we obtain a combined polaritonic and photonic gap
as a generalization of the Rabi splitting phenomenon. For typical experimental
parameters, the size of the combined gap is on the order of 25 cm^-1, up to
10^5 times the detuned gap size.
\\ ( http://arXiv.org/abs/cond-mat/0607277 , 118kb)
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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/
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Received on Thu Jul 13 2006 - 18:00:56 EST

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