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

Date: Mon, 13 Nov 2006 11:22:48 +1000 (EST)

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>

Home page: http://www.physics.uq.edu.au/people/mdavis/matts_arXiv/

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

Comments: 13 pages, 3 figures

\\

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

Comments: 4 pages, 5 figures

\\

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

Comments: 6 pages, 6 figures

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

Comments: 4 pages, 3 figures

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

Comments: 7 pages, 2 figures

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

Comments: Latex file, 12 pages

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

Comments: 5 pages, 4 figures

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

Comments: 7 pages

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

Comments: no figures

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

Comments: 4 pages, 3 figures

\\

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

Comments: 6 pages, 4 figures

\\

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

Comments: 5 pages, 3 figures

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

Comments: 4 pages, 5 figures

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

Comments: 14 pages, 5 figures

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

Comments: 4 pages, 4 figures

\\

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

Comments: 7 pages, 5 figures

\\

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

Comments: 7 pages, 15 figures

Subj-class: Atomic Physics; Optics

\\

We characterize the loading, containment and optical properties of

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

optical-gradient-dipole traps. Cold atoms are loaded from a mirror

magneto-optical trap (MMOT) centered a few hundred microns above the gold

mirror surface. Details of loading optimization are reported and perspectives

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

Authors: G.A. Muradyan and A.Zh. Muradyan

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

Comments: 5 pages, 3 figures

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

Comments: 16 pages, 15 figures. References added and typos corrected

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)

Comments: 4 pages, 2 figures

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

Comments: final version

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

Comments: 9 pages, PDF only

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

Comments: Added references, corrected typos, minor changes in text

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

Comments: 11 pages

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/ ========================================================================= 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 Mon Nov 13 2006 - 11:22:48 EST

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