# Matt's arXiv selection: week ending Friday 10th November 2006.

From: Matthew Davis <mdavis_at_physics.uq.edu.au>
Date: Mon, 13 Nov 2006 11:22:48 +1000 (EST)

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

Thirty new papers this week. One that caught my eye was from Innsbruck, where
it is reported that ultracold 87Rb2 Feshbach molecules in an optical lattice
have been transferred to more deeply bound vibrational states.

The new abstracts:

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Paper: cond-mat/0611087
Date: Fri, 3 Nov 2006 13:52:40 GMT (36kb)

Title: Nonlinear mean-field Fokker-Planck equations and their applications in
physics, astrophysics and biology
Authors: Pierre-Henri Chavanis
Subj-class: Statistical Mechanics
Journal-ref: C. R. Physique, 7, 318 (2006)
\\
We discuss a general class of nonlinear mean-field Fokker-Planck equations
[P.H. Chavanis, Phys. Rev. E, 68, 036108 (2003)] and show their applications in
different domains of physics, astrophysics and biology. These equations are
associated with generalized entropic functionals and non-Boltzmannian
distributions (Fermi-Dirac, Bose-Einstein, Tsallis,...). They furthermore
involve an arbitrary binary potential of interaction. We emphasize analogies
between different topics (two-dimensional turbulence, self-gravitating systems,
Debye-H\"uckel theory of electrolytes, porous media, chemotaxis of bacterial
populations, Bose-Einstein condensation, BMF model, Cahn-Hilliard
equations,...) which were previously disconnected. All these examples (and
probably many others) are particular cases of this general class of nonlinear
mean-field Fokker-Planck equations.
\\ ( http://arXiv.org/abs/cond-mat/0611087 , 36kb)
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Paper: cond-mat/0611091
Date: Fri, 3 Nov 2006 17:10:34 GMT (191kb)

Title: Entanglement in Correlated Fermionic Systems and Quantum Phase
Transitions
Authors: Alberto Anfossi, Paolo Giorda, and Arianna Montorsi
Comments: 14 pages, 8 figures, 2 tables
Subj-class: Strongly Correlated Electrons; Statistical Mechanics
\\
The role of two-point and multipartite entanglement at Quantum Phase
Transitions (QPTs) in correlated electron systems is investigated. We consider
a bond-charge extended Hubbard model exactly solvable in one dimension which
displays various QPTs --with two (qubits) as well as more (qudits) on-site
degrees of freedom involved. We first provide the detailed calculations that
allow to classify the QPTs according to [10]. The analysis is then carried out
by means of different measures of bipartite/multipartite quantum correlations.
It is found that all transitions ascribed to two-point correlations are
characterized by an entanglement range which diverges at the transition points.
The exponent coincides with that of the correlation length at the transitions.
We introduce the Correlation Ratio, namely the ratio of quantum mutual
information and single site entanglement. We show that at T=0 it captures the
relative role of two-point and multipartite quantum correlations at transition
points, generalizing to qudits systems the Entanglement Ratio. Moreover, a
finite value of quantum mutual information between infinitely distant sites is
seen to quantify the presence of off diagonal long range order (ODLRO) induced
by multipartite entanglement.
\\ ( http://arXiv.org/abs/cond-mat/0611091 , 191kb)
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Paper: quant-ph/0611038
Date: Fri, 3 Nov 2006 00:25:02 GMT (458kb)

Title: Stationary entanglement between two movable mirrors in a classically
driven Fabry-Perot cavity
Authors: David Vitali, Stefano Mancini, and Paolo Tombesi
\\
We consider a Fabry-Perot cavity made by two moving mirrors and driven by an
intense classical laser field. We show that stationary entanglement between two
vibrational modes of the mirrors, with effective mass of the order of
micrograms, can be generated by means of radiation pressure. The resulting
entanglement is however quite fragile with respect to temperature.
\\ ( http://arXiv.org/abs/quant-ph/0611038 , 458kb)
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Paper: quant-ph/0611040
Date: Fri, 3 Nov 2006 08:26:11 GMT (110kb)

Title: Semiclassical quantization of an N-particle Bose-Hubbard model
Authors: E.-M. Graefe and H. J. Korsch
\\
We derive a semiclassical approximation for an N-particle, two-mode
Bose-Hubbard system modeling a Bose-Einstein condensate in double-well
potential. This semiclassical description is based on the classical' dynamics
of the mean-field Gross-Pitaevskii equation and is expected to be valid for
large N. We demonstrate the possibility to reconstruct the quantum properties
of the N-particle system from the mean-field dynamics. For example, the
resulting WKB-type eigenvalues and eigenstates are found to be in very good
agreement with the exact ones, even for small values of N, both in the
subcritical and supercritical regime.
\\ ( http://arXiv.org/abs/quant-ph/0611040 , 110kb)
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Paper: physics/0611036
Date: Fri, 3 Nov 2006 16:50:39 GMT (100kb)

Title: A linear Stark shift in dressed atoms as a signal to measure a nuclear
anapole moment with a cold atom fountain or interferometer
Authors: Marie-Anne Bouchiat
Comments: Article, 4 pages, 2 figures
Subj-class: Atomic Physics
\\
We demonstrate theoretically the existence of a linear dc Stark shift of the
individual substates of an alkali atom in its ground state, dressed by a
circularly polarized laser field. It arises from the electroweak nuclear
anapole moment violating P but not T. It is characterized by the pseudoscalar
equal to the mixed product formed with the photon angular momentum and static
electric and magnetic fields. We derive the relevant left-right asymmetry with
its complete signature in a field configuration selected for a precision
measurement with cold atom beams. The 3,3 to 4,3 Cs hyperfine-transition
frequency shift amounts to 7 $\mu$Hz for a laser power of about 1 kW at 877 nm,
E=100 kV/cm and B larger than 0.5 G.
\\ ( http://arXiv.org/abs/physics/0611036 , 100kb)
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Paper: cond-mat/0611104
Date: Mon, 6 Nov 2006 18:29:21 GMT (283kb)

Title: What can ultracold Fermi gases teach us about high $T_c$ superconductors
and vice versa?
Authors: K. Levin and Qijin Chen
Comments: 4 pages, 6 figures, to appear in a special issue of Physica C for the
M2S-HTSC VIII Conference Proceedings
Subj-class: Superconductivity; Strongly Correlated Electrons
\\
We review recent developments in the field of ultracold atomic Fermi gases.
As the cold atom system evolves from BCS to Bose-Einstein condensation (BEC),
the behavior of the thermodynamics, and the particle density profiles evolves
smoothly in a way which can be well understood theoretically. In the
interesting "unitary" regime, we show that these and other data necessarily
requires the introduction of a pseudogap in the fermionic spectrum which
exhibits many striking similarities to its counterpart in underdoped high $T_c$
superconductors. We emphasize these similarities, giving an overview of the
experimental tools and key issues of common interest in both systems.
\\ ( http://arXiv.org/abs/cond-mat/0611104 , 283kb)
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Paper: cond-mat/0611109
Date: Sat, 4 Nov 2006 18:03:43 GMT (45kb)

Title: Disorder-Induced Superfluidity in Hardcore Bosons in Two Dimensions
Authors: Ji-Woo Lee, Shailesh Chandrasekharan, and Harold U. Baranger
Subj-class: Statistical Mechanics; Superconductivity
\\
We study the effect of disorder on hardcore bosons in two dimensions at the
SU(2) symmetric Heisenberg point''. We obtain our results with quantum Monte
Carlo simulations using the directed loop algorithm. In the absence of
disorder, the system has no long-range order at finite temperature due to the
enhanced symmetry. However, the introduction of a disordered potential,
uniformly distributed from -D to D, induces a finite-temperature superfluid
phase. In particular the diagonal correlation length \xi decreases but the
superfluid order-parameter correlation function becomes a power-law. A
non-monotonic finite-size behavior is noted and explained as arising due to
\xi. We provide evidence that at long distances the effects of a weak
disordered potential can be mimicked by an effective uniform potential with a
root-mean-square value: mu_eff = D/sqrt{3}. For strong disorder, the system
becomes a Bose glass insulator.
\\ ( http://arXiv.org/abs/cond-mat/0611109 , 45kb)
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Paper: cond-mat/0611126
Date: Mon, 6 Nov 2006 03:56:56 GMT (14kb)

Title: Coexistence of superfluid and Mott phases of lattice bosons
Authors: R. A. Barankov, C. Lannert, S. Vishveshwara
Subj-class: Other
\\
Recent experiments on strongly-interacting bosons in optical lattices have
revealed the co-existence of spatially-separated Mott-insulating and
number-fluctuating phases. The description of this inhomogeneous situation is
the topic of this Letter. We establish that the number-fluctuating phase forms
a superfluid trapped between the Mott-insulating regions and derive the
associated collective mode structure. We discuss the interlayer's crossover
between two- and three-dimensional behavior as a function of the lattice
parameters and estimate the critical temperatures for the transition of the
superfluid phase to a normal phase.
\\ ( http://arXiv.org/abs/cond-mat/0611126 , 14kb)
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Paper: cond-mat/0611131
Date: Mon, 6 Nov 2006 04:28:56 GMT (542kb)

Title: Can Spinor Dipolar Effects be Observed in Bose-Einstein Condensates?
Authors: Yuki Kawaguchi, Hiroki Saito, and Masahito Ueda
Subj-class: Other
\\
Weak dipolar effects in atomic Bose-Einstein condensates (BECs) have recently
been predicted to develop spin textures. However, observation of these effects
requires magnetic field as low as $\sim 10 \mu$G for spin-1 alkali BECs, so
that they are not washed out by the Zeeman effect. We present a scheme to
observe the magnetic dipole-dipole interaction in alkali BECs under a realistic
magnetic field of $\sim 100$ mG. Our scheme enables us to extract genuine
dipolar effects and should apply also to $^{52}$Cr BECs.
\\ ( http://arXiv.org/abs/cond-mat/0611131 , 542kb)
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Paper: cond-mat/0611137
Date: Mon, 6 Nov 2006 10:41:18 GMT (56kb)

Title: Nonexponential decay of Bose-Einstein condensates: a numerical study
based on the complex scaling method
Authors: Peter Schlagheck and Sandro Wimberger
Subj-class: Other
\\
We study the decay dynamics of an interacting Bose-Einstein condensate in the
presence of a metastable trapping potential from which the condensate can
escape via tunneling through finite barriers. The time-dependent decay process
is reproduced by means of the instantaneous decay rates of the condensate at a
given population of the quasi-bound state, which are calculated with the method
of complex scaling. Both for the case of a double barrier potential as well as
for the case of a tilted periodic potential, we find pronounced deviations from
a monoexponential decay behaviour which would generally be expected in the
absence of the atom-atom interaction.
\\ ( http://arXiv.org/abs/cond-mat/0611137 , 56kb)
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Paper: cond-mat/0611139
Date: Mon, 6 Nov 2006 11:21:20 GMT (11kb)

Title: Self-Consistent Theory of Bose-Condensed Systems
Authors: V.I. Yukalov
Subj-class: Statistical Mechanics
Journal-ref: Phys. Lett. A 359 (2006) 712-717
\\
In the theory of Bose-condensed systems, there exists the well known problem,
the Hohenberg-Martin dilemma of conserving versus gapless approximations. This
dilemma is analysed and it is shown that it arises because of the internal
inconsistency of the standard grand ensemble, as applied to Bose-systems with
broken global gauge symmetry. A solution of the problem is proposed, based on
the notion of representative statistical ensembles, taking into account all
constraints imposed on the system. A general approach for constructing
representative ensembles is formulated. Applying a representative ensemble to
Bose-condensed systems results in a completely self-consistent theory, both
conserving and gapless in any approximation.
\\ ( http://arXiv.org/abs/cond-mat/0611139 , 11kb)
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Paper: cond-mat/0611146
Date: Mon, 6 Nov 2006 13:08:13 GMT (364kb)

Title: Effect of interactions on the localization of a Bose-Einstein condensate
in a quasi-periodic lattice
Authors: J. E. Lye, L. Fallani, C. Fort, V. Guarrera, M. Modugno, D. S.
Wiersma, and M. Inguscio
Subj-class: Other
\\
The transport properties of a Bose-Einstein condensate in a 1D incommensurate
bichromatic lattice are investigated both theoretically and experimentally. We
observe a blockage of the center of mass motion with low atom number, and a
return of motion when the atom number is increased. Solutions of the
Gross-Pitaevskii equation show how the localization due to the quasi-disorder
introduced by the incommensurate bichromatic lattice is affected by the
interactions.
\\ ( http://arXiv.org/abs/cond-mat/0611146 , 364kb)
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Paper: cond-mat/0611149
Date: Mon, 6 Nov 2006 13:31:03 GMT (134kb)

Title: Linear "ship waves" generated in stationary flow of a Bose-Einstein
condensate past an obstacle
Authors: Yu.G. Gladush, G.A. El, A. Gammal, and A.M. Kamchatnov
Subj-class: Other
\\
Using stationary solutions of the linearized two-dimensional Gross-Pitaevskii
equation, we describe the ship wave'' pattern occurring in the supersonic
flow of a Bose-Einstein condensate past an obstacle. It is shown that these
ship waves'' are generated outside the Mach cone. The developed analytical
theory is confirmed by numerical simulations of the flow past body problem in
the frame of the full non-stationary Gross-Pitaevskii equation.
\\ ( http://arXiv.org/abs/cond-mat/0611149 , 134kb)
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Paper: physics/0611058
Date: Mon, 6 Nov 2006 17:17:27 GMT (402kb)

Title: Detection of NMR signals with a radio-frequency atomic magnetometer
Authors: I. M. Savukov, S. J. Seltzer and M. V. Romalis
Subj-class: Atomic Physics; Chemical Physics
\\
We demonstrate detection of proton NMR signals with a radio frequency atomic
magnetometer tuned to the NMR frequency of 62 kHz. High-frequency operation of
the atomic magnetometer makes it relatively insensitive to ambient magnetic
field noise. We obtain magnetic field sensitivity of 7 fT/Hz$^{1/2}$ using only
a thin aluminum shield. We also derive an expression for the fundamental
sensitivity limit of a surface inductive pick-up coil as a function of
frequency and find that an atomic rf magnetometer is intrinsically more
sensitive than a coil of comparable size for frequencies below about 50 MHz.
\\ ( http://arXiv.org/abs/physics/0611058 , 402kb)
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Paper: cond-mat/0611171
Date: Tue, 7 Nov 2006 07:05:51 GMT (19kb)

Title: Symmetry and inert states of spin Bose Condensates
Authors: S.-K. Yip
Subj-class: Superconductivity
\\
We construct the list of all possible inert states of spin Bose condensates
for $S \le 4$. In doing so, we also obtain their symmetry properties. These
results are applied to classify line defects of these spin condensates at zero
magnetic field.
\\ ( http://arXiv.org/abs/cond-mat/0611171 , 19kb)
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Paper: quant-ph/0611067
Date: Mon, 6 Nov 2006 22:22:29 GMT (193kb)

Title: A Straightforward Introduction to Continuous Quantum Measurement
Authors: Kurt Jacobs, Daniel A. Steck
Comments: 24 pages, 3 eps figues. To appear in Contemporary Physics
\\
We present a pedagogical treatment of the formalism of continuous quantum
measurement. Our aim is to show the reader how the equations describing such
measurements are derived and manipulated in a direct manner. We also give
elementary background material for those new to measurement theory, and
describe further various aspects of continuous measurements that should be
helpful to those wanting to use such measurements in applications.
Specifically, we use the simple and direct approach of generalized measurements
to derive the stochastic master equation describing the continuous measurements
of observables, give a tutorial on stochastic calculus, treat multiple
observers and inefficient detection, examine a general form of the measurement
master equation, and show how the master equation leads to information gain and
disturbance. To conclude, we give a detailed treatment of imaging the resonance
fluorescence from a single atom as a concrete example of how a continuous
position measurement arises in a physical system.
\\ ( http://arXiv.org/abs/quant-ph/0611067 , 193kb)
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Paper: quant-ph/0611073
Date: Tue, 7 Nov 2006 14:41:32 GMT (285kb)

Title: Stationary light pulses in ultra cold atomic gasses
Authors: Kristian Rymann Hansen and Klaus Molmer
\\
We present a theoretical treatment of electromagnetically induced
transparency and light storage using standing wave coupling fields in a medium
comprised of stationary atoms, such as an ultra cold atomic gas or a solid
state medium. We show that it is possible to create stationary pulses of light
which have a qualitatively different behavior than in the case of a thermal gas
medium, offering greater potential for quantum information processing
applications.
\\ ( http://arXiv.org/abs/quant-ph/0611073 , 285kb)
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Paper: quant-ph/0611078
Date: Tue, 7 Nov 2006 17:47:43 GMT (88kb)

Title: Stability and entanglement in optical-atomic amplification of trapped
atoms: the role of atomic collisions
Authors: V. V. Fran\c{c}a and G. A. Prataviera
\\
Atomic collisions are included in an interacting system of optical fields and
trapped atoms allowing field amplification. We study the effects of collisions
on the system stability. Also a study of the degree of entanglement between
atomic and optical fields is made. We found that, for an atomic field initially
in a vacuum state and optical field in a coherent state, the degree of
entanglement does not depend on the optical field intensity or phase. We show
that in conditions of exponential instability the system presents at long times
two distinct stationary degree of entanglement with collisions affecting only
one of them.
\\ ( http://arXiv.org/abs/quant-ph/0611078 , 88kb)
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Paper: physics/0611067
Date: Tue, 7 Nov 2006 06:39:45 GMT (261kb)

Title: $^{87}$Sr lattice clock with inaccuracy below 10$^{-15}$
Authors: Martin M. Boyd, Andrew D. Ludlow, Sebastian Blatt, Seth M. Foreman,
Tetsuya Ido, Tanya Zelevinsky, and Jun Ye
Comments: 4 pages, 4 figures, 2 tables
Subj-class: Atomic Physics; General Physics
\\
Aided by ultra-high resolution spectroscopy, the overall systematic
uncertainty of the $^{1}S_{0}$-$^{3}P_{0}$ clock resonance for lattice-confined
$^{87}$Sr has been characterized to $9\times10^{-16}$. This uncertainty is at a
level similar to the Cs-fountain primary standard, while the potential
stability for the lattice clocks exceeds that of Cs. The absolute frequency of
the clock transition has been measured to be 429,228,004,229,874.0(1.1) Hz,
where the $2.5\times10^{-15}$ fractional uncertainty represents the most
accurate measurement of a neutral-atom-based optical transition frequency to
date.
\\ ( http://arXiv.org/abs/physics/0611067 , 261kb)
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Paper: cond-mat/0611206
Date: Wed, 8 Nov 2006 11:36:46 GMT (812kb)

Title: Measuring the one-particle excitations of ultracold fermionic atoms by
stimulated Raman spectroscopy
Authors: Tung-Lam Dao, Antoine Georges, Jean Dalibard, Christophe Salomon,
Iacopo Carusotto
Subj-class: Other
\\
We propose a Raman spectroscopy technique which is able to probe the
one-particle Green's function, the Fermi surface, and the quasiparticles of a
gas of strongly interacting ultracold atoms. We give quantitative examples of
experimentally accessible spectra. The efficiency of the method is validated by
means of simulated images for the case of a usual Fermi liquid as well as for
more exotic states: specific signatures of e.g. a d-wave pseudo-gap are clearly
visible.
\\ ( http://arXiv.org/abs/cond-mat/0611206 , 812kb)
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Paper: cond-mat/0611222
Date: Wed, 8 Nov 2006 18:18:54 GMT (34kb)

Title: Coherent optical transfer of Feshbach molecules to a lower vibrational
state
Authors: K. Winkler, F. Lang, G. Thalhammer, P. v. d. Straten, R. Grimm, and J.
Hecker Denschlag
Subj-class: Other
\\
Using the technique of stimulated Raman adiabatic passage (STIRAP) we have
coherently transferred ultracold 87Rb2 Feshbach molecules into a more deeply
bound vibrational quantum level. Our measurements indicate a high transfer
efficiency of up to 87%. As the molecules are held in an optical lattice with
not more than a single molecule per lattice site, inelastic collisions between
the molecules are suppressed and we observe long molecular lifetimes of about 1
s. Using STIRAP we have created quantum superpositions of the two molecular
states and tested their coherence interferometrically. These results represent
an important step towards Bose-Einstein condensation (BEC) of molecules in the
vibrational ground state.
\\ ( http://arXiv.org/abs/cond-mat/0611222 , 34kb)
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Paper: cond-mat/0611227
Date: Wed, 8 Nov 2006 20:28:59 GMT (952kb)

Title: Localization and Anomalous Transport in a 1-D Soft Boson Optical Lattice
Authors: A. K. Tuchman, W. Li, H. Chien, S. Dettmer, M. A. Kasevich
Subj-class: Mesoscopic Systems and Quantum Hall Effect
\\
We study the dynamics of Bose-Einstein condensed atoms in a 1-D optical
lattice potential in a regime where the collective (Josephson) tunneling energy
is comparable with the on-site interaction energy, and the number of particles
per lattice site is mesoscopically large. By directly imaging the motion of
atoms in the lattice, we observe an abrupt suppression of atom transport
through the array for a critical ratio of these energies, consistent with
quantum fluctuation induced localization. Directly below the onset of
localization, the frequency of the observed superfluid transport can be
explained by a phonon excitation but deviates substantially from that predicted
by the hydrodynamic/Gross-Pitaevskii equations.
\\ ( http://arXiv.org/abs/cond-mat/0611227 , 952kb)
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Paper: quant-ph/0611088
Date: Wed, 8 Nov 2006 17:39:49 GMT (47kb)

Title: Quantum superchemistry in an output coupler of coherent matter waves
Authors: Hui Jing and Jing Cheng
Comments: 3 figures, accepted by Phys.Rev.A (submitted to prl in July,
transferred to pra in Sep. and accepted in Nov.)
\\
We investigate the quantum superchemistry or Bose-enhanced atom-molecule
conversions in a coherent output coupler of matter waves, as a simple
generalization of the two-color photo-association. The stimulated effects of
molecular output step and atomic revivals are exhibited by steering the rf
output couplings. The quantum noise-induced molecular damping occurs near a
total conversion in a levitation trap. This suggests a feasible two-trap scheme
to make a stable coherent molecular beam.
\\ ( http://arXiv.org/abs/quant-ph/0611088 , 47kb)
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Paper: quant-ph/0611093
Date: Wed, 8 Nov 2006 19:31:09 GMT (642kb)

Title: Quantum processing photonic states in optical lattices
Authors: Christine A. Muschik, Ines de Vega, Diego Porras, J. Ignacio Cirac
\\
The mapping of photonic states to collective excitations of atomic ensembles
is a powerful tool which finds an useful application in the realization of
quantum memories and quantum repeaters. In this work we show that cold atoms in
optical lattices can be used to perform an entangling unitary operation on the
transferred atomic excitations. After the release of the quantum atomic state,
our protocol results in a deterministic two qubit gate for photons. The
proposed scheme is feasible with current experimental techniques and robust
against the dominant sources of noise.
\\ ( http://arXiv.org/abs/quant-ph/0611093 , 642kb)
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Paper: cond-mat/0611229
Date: Wed, 8 Nov 2006 22:26:24 GMT (366kb)

Title: Magnetostriction in the Bose-Einstein Condensate quantum magnet
NiCl2-4SC(NH2)2
Authors: V. S. Zapf, V. F. Correa, C. D. Batista, T. P. Murphy, E. D. Palm, M.
Jaime, S. Tozer, A. Lacerda, A. Paduan-Filho
Comments: Submitted to Journal of Applied Physics
Subj-class: Strongly Correlated Electrons; Materials Science
\\
The quantum magnet NiCl$_2$-4SC(NH$_2$)$_2$ is a candidate for observing
Bose-Einstein Condensation of spin degrees of freedom in applied magnetic
fields. An XY antiferromagnetic ordered state occurs in a dome-shaped region of
the temperature-field phase diagram between H$_{c1}$ = 2.1 T and H$_{c2}$ =
12.6 T and below 1.2 K. BEC corresponds to the field-induced quantum phase
transition into the ordered state. We investigate magnetostriction in single
crystals of this compound at dilution refrigerator temperatures in magnetic
fields up to 18 T, and as a function of magnetic field angle. We show that
significant changes in the lattice parameters are induced by magnetic fields,
and argue that these result from antiferromagnetic couplings between the Ni
spins along the tetragonal c-axis. The magnetic phase diagram as a function of
temperature, field, and field angle can be extracted from these data. We
discuss the implications of these results to Bose-Einstein Condensation in this
system.
\\ ( http://arXiv.org/abs/cond-mat/0611229 , 366kb)
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Paper: cond-mat/0611230
Date: Thu, 9 Nov 2006 07:18:19 GMT (16kb)

Title: Classifying Vortices in S=3 Bose-Einstein Condensates
Authors: Ryan Barnett, Ari Turner, Eugene Demler
Subj-class: Strongly Correlated Electrons
\\
Motivated by the recent realization of a $^{52}$Cr Bose-Einstein condensate,
we consider the phase diagram of a general spin-three condensate as a function
of its scattering lengths. We classify each phase according to its reciprocal
spinor,'' using a method developed in a previous work. We show that such a
classification can be naturally extended to describe the vortices for a spinor
condensate by using the topological theory of defects. To illustrate, we
systematically describe the types of vortex excitations for each phase of the
spin-three condensate.
\\ ( http://arXiv.org/abs/cond-mat/0611230 , 16kb)
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Paper: cond-mat/0611259
Date: Thu, 9 Nov 2006 17:51:43 GMT (193kb)

Title: Acoustic attenuation rate in the Fermi-Bose model with a finite-range
fermion-fermion interaction
Authors: Bogdan Mihaila, Sergio Gaudio, Kevin S. Bedell, Krastan B. Blagoev,
and Eddy Timmermans
Report-no: LA-UR-05-2040
Subj-class: Other
\\
We study the acoustic attenuation rate in the Fermi-Bose model describing a
mixtures of bosonic and fermionic atom gases. We demonstrate the dramatic
change of the acoustic attenuation rate as the fermionic component is evolved
through the BEC-BCS crossover, in the context of a mean-field model applied to
a finite-range fermion-fermion interaction at zero temperature, such as
discussed previously by M.M. Parish et al. [Phys. Rev. B 71, 064513 (2005)] and
B. Mihaila et al. [Phys. Rev. Lett. 95, 090402 (2005)]. The shape of the
acoustic attenuation rate as a function of the boson energy represents a
signature for superfluidity in the fermionic component.
\\ ( http://arXiv.org/abs/cond-mat/0611259 , 193kb)
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Paper: quant-ph/0611097
Date: Thu, 9 Nov 2006 04:08:21 GMT (384kb)

Title: Ultraslow Propagation of a Squeezed Vacuum with Electromagnetically
Induced Transparency
Authors: Daisuke Akamatsu, Yoshihiko Yokoi, Takahito Tanimura, Akira Furusawa,
and Mikio Kozuma
\\
We have succeeded in observing ultraslow propagation of squeezed vacuum
pulses with electromagnetically induced transparency. Squeezed vacuum pulses
(probe) were incident on a $^{87}$Rb gas cell together with an intense coherent
light (control). Not a photon counting, but a homodyne method, which is
sensitive to the vacuum state, was employed for detecting the probe pulse
passing through the cell. A delay of 1.3 $\mu$s was observed for a probe pulse
having a temporal width of 12 $\mu$s.
\\ ( http://arXiv.org/abs/quant-ph/0611097 , 384kb)
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Paper: quant-ph/0611104
Date: Thu, 9 Nov 2006 18:13:34 GMT (39kb)

Title: Force on a neutral atom near conducting microstructures
Authors: Claudia Eberlein and Robert Zietal
\\
We derive the non-retarded energy shift of a neutral atom for two different
geometries. For an atom close to a cylindrical wire we find an integral
representation for the energy shift, give asymptotic expressions, and
interpolate numerically. For an atom close to a semi-infinite halfplane we
determine the exact Green's function of the Laplace equation and use it derive
the exact energy shift for an arbitrary position of the atom. These results can
be used to estimate the energy shift of an atom close to etched microstructures
that protrude from substrates.
\\ ( http://arXiv.org/abs/quant-ph/0611104 , 39kb)
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Paper: physics/0611092
Date: Thu, 9 Nov 2006 14:53:49 GMT (698kb)

Title: All-optical atom surface traps implemented with one-dimensional planar
diffractive microstructures
Authors: O. Alloschery, R. Mathevet, J. Weiner
Subj-class: Atomic Physics; Optics
\\
all-optical atom traps implemented by diffractive focusing with one-dimensional
(1D) microstructures milled on gold films. These on-chip Fresnel lenses with
focal lengths of the order of a few hundred microns produce
magneto-optical trap (MMOT) centered a few hundred microns above the gold
for future development of these structures are discussed.
\\ ( http://arXiv.org/abs/physics/0611092 , 698kb)
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Replacements:

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Paper: cond-mat/0610797
replaced with revised version Fri, 3 Nov 2006 19:48:32 GMT (27kb)

Title: Theory of Critical Temperature Adiabatic Change for Ideal Gas
Bose-Einstein Condensation in Optical Lattices
Subj-class: Other; Statistical Mechanics
\\ ( http://arXiv.org/abs/cond-mat/0610797 , 27kb)
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\\
Paper (*cross-listing*): nlin.PS/0604044
replaced with revised version Thu, 2 Nov 2006 22:51:44 GMT (152kb)

Title: Oblique dark solitons in supersonic flow of a Bose-Einstein condensate
Authors: G.A. El, A. Gammal, A.M. Kamchatnov
Subj-class: Pattern Formation and Solitons; Soft Condensed Matter
Journal-ref: Phys. Rev. Lett. 97, 180405 (2006)
DOI: 10.1103/PhysRevLett.97.180405
\\ ( http://arXiv.org/abs/nlin/0604044 , 152kb)
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\\
Paper: cond-mat/0510672
replaced with revised version Sun, 5 Nov 2006 21:28:45 GMT (59kb)

Title: Properties of the strongly paired fermionic condensates
Authors: J. Levinsen and V. Gurarie
Subj-class: Superconductivity; Statistical Mechanics
Journal-ref: Phys. Rev. A 73, 053607 (2006)
\\ ( http://arXiv.org/abs/cond-mat/0510672 , 59kb)
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\\
Paper: cond-mat/0605751
replaced with revised version Mon, 6 Nov 2006 18:12:14 GMT (237kb)

Title: Universal phase diagram of a strongly interacting Fermi gas with
unbalanced spin populations
Authors: Fr\'{e}d\'{e}ric Chevy (LKB - Lhomond)
Proxy: ccsd ccsd-00077712
Subj-class: Statistical Mechanics
\\ ( http://arXiv.org/abs/cond-mat/0605751 , 237kb)
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\\
Paper: cond-mat/0606288
replaced with revised version Mon, 6 Nov 2006 04:52:02 GMT (48kb)

Title: Spontaneous Circulation in Ground-State Spinor Dipolar Bose-Einstein
Condensates
Authors: Yuki Kawaguchi, Hiroki Saito, and Masahito Ueda
Subj-class: Other
Journal-ref: Phys. Rev. Lett. 97, 130404 (2006)
DOI: 10.1103/PhysRevLett.97.130404
\\ ( http://arXiv.org/abs/cond-mat/0606288 , 48kb)
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\\
Paper: cond-mat/0606322
replaced with revised version Mon, 6 Nov 2006 14:27:24 GMT (750kb)

Title: Finite Temperature Phase Diagram of a Two-Component Fermi Gas with
Density Imbalance
Authors: Lianyi He, Meng Jin and Pengfei Zhuang
Comments: 12 pages, 10 figures, accepted for publication in PRB
Subj-class: Superconductivity; Other; Statistical Mechanics; Atomic Physics
\\ ( http://arXiv.org/abs/cond-mat/0606322 , 750kb)
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\\
Paper: quant-ph/0610141
replaced with revised version Sat, 4 Nov 2006 14:02:37 GMT (156kb)

Title: High-temperature Bose-Einstein condensation of polaritons: realization
under the intracavity laser pumping of matter condition
Authors: V. A. Averchenko, A. P. Alodjants, S. M. Arakelian, S. N. Bagayev, E.
A. Vinogradov, V. S. Egorov, A. I. Stolyarov, I. A. Chekhonin
Journal-ref: Kvantovaya Elektronika (Quantum Elactronics), V.36 (2006)
pp.532-538
\\ ( http://arXiv.org/abs/quant-ph/0610141 , 156kb)
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\\
Paper: cond-mat/0607147
replaced with revised version Tue, 7 Nov 2006 12:05:07 GMT (517kb)

Title: Vortex Core Structure in Neutral Fermion Superfluids with Population
Imbalance
Authors: M. Takahashi, T. Mizushima, M. Ichioka, K. Machida
Comments: 5 pages, 5 figures, replaced by the version to appear in PRL
Subj-class: Superconductivity
Journal-ref: Phys. Rev. Lett. 97, 180407 (2006)
\\ ( http://arXiv.org/abs/cond-mat/0607147 , 517kb)
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Paper (*cross-listing*): hep-ph/0512357
replaced with revised version Tue, 7 Nov 2006 18:55:30 GMT (615kb)

Title: Two- and Three-Particle Correlations in q,p-Bose Gas Model
Authors: Alexandre M. Gavrilik
Comments: Published in SIGMA (Symmetry, Integrability and Geometry: Methods and
Applications) at http://arxiv.org/abs/nlin.SI/0610011
Subj-class: High Energy Physics - Phenomenology; Statistical Mechanics
Journal-ref: SIGMA 2 (2006), 074, 12 pages
\\ ( http://arXiv.org/abs/hep-ph/0512357 , 182kb)
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\\
Paper: cond-mat/0607253
replaced with revised version Tue, 7 Nov 2006 23:02:59 GMT (45kb)

Title: Classifying Novel Phases of Spinor Atoms
Authors: Ryan Barnett, Ari Turner, Eugene Demler
Subj-class: Strongly Correlated Electrons
Journal-ref: Phys. Rev. Lett. 97, 180412 (2006)
\\ ( http://arXiv.org/abs/cond-mat/0607253 , 45kb)
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\\
Paper: cond-mat/0608282
replaced with revised version Wed, 8 Nov 2006 19:12:58 GMT (301kb)

Title: Thermodynamics of the BCS-BEC crossover
Authors: R. Haussmann, W. Rantner, S. Cerrito and W. Zwerger
Comments: Revised version, including comparison with recent field-theoretic
results
Subj-class: Statistical Mechanics
\\ ( http://arXiv.org/abs/cond-mat/0608282 , 301kb)
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\\
Paper: cond-mat/0609195
replaced with revised version Wed, 8 Nov 2006 03:10:02 GMT (997kb)

Title: Bosons in Disordered Optical Potentials
Authors: Pearl J.Y. Louis and Makoto Tsubota
Comments: 4 pages, 4 figures (low res) v2 Title,Abstract,Introduction: changes;
Figure 3: Add label to axis
Subj-class: Disordered Systems and Neural Networks
\\ ( http://arXiv.org/abs/cond-mat/0609195 , 997kb)
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\\
Paper: cond-mat/0611094
replaced with revised version Wed, 8 Nov 2006 22:48:45 GMT (25kb)

Title: Alleviation of the Fermion-sign problem by optimization of many-body
wave functions
Authors: C. J. Umrigar, Julien Toulouse, Claudia Filippi, S. Sorella, R. G.
Hennig
Subj-class: Other; Materials Science
\\ ( http://arXiv.org/abs/cond-mat/0611094 , 25kb)
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\\
Paper: quant-ph/0605123
replaced with revised version Thu, 9 Nov 2006 05:55:40 GMT (9kb)

Title: Exact Solutions of a Non-Polynomially Nonlinear Schrodinger Equation
Authors: R. Parwani and H. S. Tan
Subj-class: Quantum Physics; Pattern Formation and Solitons
\\ ( http://arXiv.org/abs/quant-ph/0605123 , 9kb)
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\\
Paper: physics/0610027
replaced with revised version Thu, 9 Nov 2006 13:50:30 GMT (913kb)

Title: Transport of launched cold atoms with a laser guide and pulsed magnetic
fields
Authors: Matthew J Pritchard, Aidan S Arnold, Simon L Cornish, David W
Hallwood, Chris V S Pleasant and Ifan G Hughes
Comments: 18 pages 11 figures. To appear in New J. Phys. Original version
modified to include referee's improvements
Subj-class: Atomic Physics; Optics
\\ ( http://arXiv.org/abs/physics/0610027 , 913kb)
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Till next week,
Matt.

--
=========================================================================
Dr M. J. Davis,               Senior Lecturer in Physics
School of Physical Sciences,  email: mdavis_at_physics.uq.edu.au
University of Queensland,     ph   : +61 7 334 69824
Brisbane, QLD 4072,           fax  : +61 7 336 51242
Australia.                    http://www.physics.uq.edu.au/people/mdavis/
=========================================================================
Matt's arXiv selection: weekly summary of cold-atom papers from arXiv.org
http://www.physics.uq.edu.au/people/mdavis/matts_arXiv/
=========================================================================
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Received on Mon Nov 13 2006 - 11:22:48 EST

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