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

Date: Wed, 20 May 2009 16:57:50 +1000

Date: Wed, 20 May 2009 16:57:50 +1000

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

Dear subscribers,

Simon Haine deserves the credit for preparing this email. There are 14 new

preprints and 4 replacements:

------------------------------------------------------------------------------

\\

arXiv:0903.3552

Date: Fri, 20 Mar 2009 15:47:13 GMT (405kb)

Title: Cavity QED in a molecular ion trap

Authors: D. I. Schuster, Lev S. Bishop, I. L. Chuang, D. DeMille, R. J.

Schoelkopf

Categories: cond-mat.mes-hall cond-mat.supr-con quant-ph

Comments: 4 pages, 1 figure

\\

We propose an approach for studying quantum information and performing high

resolution spectroscopy of rotational states of trapped molecular ions using an

on-chip superconducting microwave resonator. Molecular ions have several

advantages over neutral molecules. Ions can be loaded into deep (1 eV) RF traps

and are trapped independent of the electric dipole moment of their rotational

transition. Their charge protects them from motional dephasing and prevents

collisional loss, allowing 1 s coherence times when used as a quantum memory,

with detection of single molecules possible in <10 ms. An analysis of the

detection efficiency and coherence properties of the molecules is presented.

\\ ( http://arxiv.org/abs/0903.3552 , 405kb)

------------------------------------------------------------------------------

\\

arXiv:0903.3520

Date: Fri, 20 Mar 2009 13:40:11 GMT (178kb)

Title: Autler-Townes effect in the D1-line hyperfine structure of an alkali

atom

Authors: A.S.Sheremet, O.S.Mishina, N.V.Larionov, D.V.Kupriyanov

Categories: quant-ph

Comments: 12 pages, 5 figures

\\

We consider the Autler-Townes effect when a strong coupling field is applied

in the hyperfine manifold of an alkali atom. Explicit solution is obtained in

the case of the D1-line. We show how the hyperfine interaction modifies the

dressing effects associated with the strong field as well as the sample

susceptibility with respect to the probe mode. Particularly, if the strong

field is far detuned from the atomic resonance line the Autler-Townes structure

differs significantly from the prediction of the Lambda-type approximation. We

also find that tuning the strong field in between the upper state hyperfine

components enhances the Autler-Townes effect. The results are discussed in the

context of quantum memory protocols based on the stimulated Raman process or

EIT effect.

\\ ( http://arxiv.org/abs/0903.3520 , 178kb)

------------------------------------------------------------------------------

\\

arXiv:0903.3511

Date: Fri, 20 Mar 2009 19:53:54 GMT (450kb)

Title: Large Momentum Beamsplitter using Bloch Oscillations

Authors: Pierre Clad\'e (LKB - Jussieu), Sa\"ida Guellati-Kh\'elifa (LKB -

Jussieu), Fran\c{c}ois Nez (LKB - Jussieu), Fran\c{c}ois Biraben (LKB -

Jussieu)

Categories: physics.atom-ph

\\

The sensitivity of an inertial sensor based on an atomic interfermometer is

proportional to the velocity separation of atoms in the two arms of the

interferometer. In this paper we describe how Bloch oscillations can be used to

increase this separation and to create a large momentum transfer (LMT)

beamsplitter. We experimentally demonstrate a separation of 10 recoil

velocities. Light shifts during the acceleration introduce phase fluctuations

which can reduce the contrast of the interferometer. We precisely calculate

this effect and demonstrate that it can be significantly reduced by using a

suitable combination of LMT pulses. We finally show that this method seems to

be very promising to realize LMT beamsplitter with several 10s of recoil and a

very good efficiency.

\\ ( http://arxiv.org/abs/0903.3511 , 450kb)

------------------------------------------------------------------------------

\\

arXiv:0903.3429

Date: Thu, 19 Mar 2009 21:41:23 GMT (87kb)

Title: How Marius Was Right and Galileo Was Wrong Even Though Galileo Was Right

and Marius Was Wrong

Authors: Christopher M. Graney

Categories: physics.hist-ph

Comments: Or, how telescopic observations in the early 17th century supported

the Tychonic geocentric theory and how Simon Marius realized this

\\

Astronomers in the early 17th century misunderstood the images of stars that

they saw in their telescopes. For this reason, the data a skilled observer of

that time acquired via telescopic observation of the heavens appeared to

support a geocentric Tychonic (or semi-Tychonic) world system, and not a

heliocentric Copernican world system. Galileo Galilei made steps in the

direction of letting observations lead him towards a Tychonic or semi-Tychonic

world system. However, he ultimately backed the Copernican system, against the

data he had on hand. By contrast, the German astronomer Simon Marius understood

that data acquired by telescopic observation supported a Tychonic world system.

\\ ( http://arxiv.org/abs/0903.3429 , 87kb)

------------------------------------------------------------------------------

\\

arXiv:0903.3863

Date: Mon, 23 Mar 2009 13:43:17 GMT (110kb)

Title: Nonlinear dynamics of ultracold gases in double-well lattices

Authors: V.I. Yukalov and E.P. Yukalova

Categories: cond-mat.stat-mech cond-mat.other

Comments: Latex file, 15 pages, 3 figures

Journal-ref: Laser Phys. Lett. 6 (2009) 235-241

\\

An ultracold gas is considered, loaded into a lattice, each site of which is

formed by a double-well potential. Initial conditions, after the loading,

correspond to a nonequilibrium state. The nonlinear dynamics of the system,

starting with a nonequilibrium state, is analysed in the local-field

approximation. The importance of taking into account attenuation, caused by

particle collisions, is emphasized. The presence of this attenuation

dramatically influences the system dynamics.

\\ ( http://arxiv.org/abs/0903.3863 , 110kb)

------------------------------------------------------------------------------

\\

arXiv:0903.3867

Date: Mon, 23 Mar 2009 14:37:15 GMT (14kb)

Title: Absence of a Direct Superfluid to Mott Insulator Transition in

Disordered Bose Systems

Authors: L. Pollet, N.V. Prokof'ev, B. V. Svistunov, M. Troyer

Categories: cond-mat.stat-mech cond-mat.other

Comments: 4 pages, 3 figures

\\

We present a rigorous analytic proof of the absence of a direct quantum phase

transition between a superfluid and a Mott insulator in a commensurate bosonic

system with generic bounded disorder. The theorem is illustrated by quantum

Monte Carlo simulations for the Bose-Hubbard model, from which we deduce an

even stronger result: The critical disorder strength, $\Delta_c$, corresponding

to the onset of disorder-induced superfluidity, satisfies the relation

$\Delta_c > E_{\rm g/2}$, with $E_{\rm g/2}$ the half-width of the Mott gap in

the pure system.

\\ ( http://arxiv.org/abs/0903.3867 , 14kb)

------------------------------------------------------------------------------

\\

arXiv:0903.3896

Date: Mon, 23 Mar 2009 16:22:08 GMT (926kb)

Title: An integrated atom detector: single atoms and photon statistics

Authors: Dennis Heine, Marco Wilzbach, Thomas Raub, Bj\"orn Hessmo, and J\"org

Schmiedmayer

Categories: quant-ph

Comments: 4 pages, 4 figures

Journal-ref: Phys. Rev. A 79, 021804 (2009)

DOI: 10.1103/PhysRevA.79.021804

\\

We demonstrate a robust fiber-optics-based fluorescence detector, fully

integrated on an atom chip, which detects single atoms propagating in a guide

with 66% efficiency. We characterize the detector performance and the atom flux

by analyzing the photon statistics. Near-perfect photon antibunching proves

that single atoms are detected, and allows us to study the second-order

intensity correlation function of the fluorescence over three orders of

magnitude in atomic density.

\\ ( http://arxiv.org/abs/0903.3896 , 926kb)

------------------------------------------------------------------------------

\\

arXiv:0903.3635

Date: Mon, 23 Mar 2009 07:13:58 GMT (22kb)

Title: Dynamics of Cold Atoms Crossing a One-Way Barrier

Authors: Jeremy J. Thorn, Elizabeth A. Schoene, Tao Li, and Daniel A. Steck

Categories: physics.atom-ph

Comments: 20 pages, 19 figures

\\

We implemented an optical one-way potential barrier that allows ultracold

$^{87}$Rb atoms to transmit through when incident on one side of the barrier

but reflect from the other. This asymmetric barrier is a realization of

Maxwell's demon, which can be employed to produce phase-space compression and

has implications for cooling atoms and molecules not amenable to standard

laser-cooling techniques. The barrier comprises two focused, Gaussian laser

beams that intersect the focus of a far-off-resonant, single-beam optical

dipole trap that holds the atoms. The main barrier beam presents a

state-dependent potential to incident atoms, while the repumping barrier beam

optically pumps atoms to a trapped state. We investigated the robustness of the

barrier asymmetry to changes in the barrier beam separation, the initial atomic

potential energy, the intensity of the second beam, and the detuning of the

first beam. We performed simulations of the atomic dynamics in the presence of

the barrier, showing that the initial three dimensional momentum distribution

plays a significant role, and that light-assisted collisions are likely the

dominant loss mechanism. We also carefully examined the relationship to

Maxwell's demon and explicitly accounted for the apparent decrease in entropy

for our particular system.

\\ ( http://arxiv.org/abs/0903.3635 , 1607kb)

------------------------------------------------------------------------------

\\

arXiv:0903.4058

Date: Tue, 24 Mar 2009 13:46:08 GMT (55kb)

Title: Wannier-function approach to the Interaction Effects in a Bose-Einstein

Condensate on an Optical Lattice: Implications for the Bose-Hubbard Model

Authors: Z. X. Liang, B. B. Hu, and Biao Wu

Categories: cond-mat.str-el

Comments: 4 pages, 3 figures

\\

We show that one can properly take into account of the interaction effects

and construct a set of orthonormal Wannier functions for a Bose-Einstein

condensate in an optical lattice. These interaction-dependent Wannier functions

are used to compute the tunneling rate $J$ and the on-site repulsion $U$ in the

Bose-Hubbard model. Both parameters are found to be substantially different

from ones calculated with the single-particle Wannier functions. Our numerical

results of $U$ are found in good agreement with the measured on-site energy in

a recent experiment [Campbell {\it et al.} Science {\bf 314}, 281 (2006)].

\\ ( http://arxiv.org/abs/0903.4058 , 55kb)

------------------------------------------------------------------------------

\\

arXiv:0903.3999

Date: ?? (??kb)

Title: Correlation Measurement of Squeezed Light

Authors: Leonid A. Krivitsky, Ulrik L. Andersen, Ruifang Dong, Alexander Huck,

Christoffer Wittmann, and Gerd Leuchs

Categories: quant-ph

Journal-ref: Phys. Rev. A 79, 033828 (2009)

\\

We study the implementation of a correlation measurement technique for the

characterization of squeezed light which is nearly free of electronic noise.

With two different sources of squeezed light, we show that the sign of the

covariance coefficient, revealed from the time resolved correlation data, is

witnessing the presence of squeezing in the system. Furthermore, we estimate

the degree of squeezing using the correlation method and compare it to the

standard homodyne measurement scheme. We show that the role of electronic

detector noise is minimized using the correlation approach as opposed to

homodyning where it often becomes a crucial issue.

\\ ( http://arxiv.org/abs/0903.3999 , 294kb)

------------------------------------------------------------------------------

\\

arXiv:0903.4234

Date: Wed, 25 Mar 2009 04:39:04 GMT (138kb)

Title: Cold-atoms on a two-dimensional square optical lattice with an

alternating potential

Authors: Huaiming Guo, Yuchuan Wen, and Shiping Feng

Categories: cond-mat.str-el

Comments: 4 pages, 4 figures

Journal-ref: Physical Review A 79,035401(2009)

DOI: 10.1103/PhysRevA.79.035401

\\

The cold-atom on a two-dimensional square optical lattice is studied within

the hard-core boson Hubbard model with an alternating potential. In terms of

the quantum Monte Carlo method, it is shown explicitly that a supersolid phase

emerges due to the presence of the alternating potential. For the weak

alternating potential, the supersolid state appears for the whole range of

hard-core boson densities except the half-filling case, where the system is a

Mott insulator. However, for the strong alternating potential, besides the

supersolid and Mott insulating states, a charge density wave phase appears.

\\ ( http://arxiv.org/abs/0903.4234 , 138kb)

------------------------------------------------------------------------------

\\

arXiv:0903.4192

Date: Tue, 24 Mar 2009 20:46:47 GMT (625kb)

Title: Atom interferometers with scalable enclosed area

Authors: Holger Mueller, Sheng-wey Chiow, Sven Herrmann, and Steven Chu

Categories: physics.atom-ph cond-mat.other physics.optics

Comments: 4 pages, 5 figures

\\

Bloch oscillations (i.e., coherent acceleration of matter waves by an optical

lattice) and Bragg diffraction are integrated into light-pulse atom

interferometers with large momentum splitting between the interferometer arms,

and hence enhanced sensitivity. Simultaneous acceleration of both arms in the

same internal states suppresses systematic effects, and simultaneously running

a pair of interferometers suppresses the effect of vibrations. Ramsey-Bord\'e

interferometers using four such Bloch-Bragg-Bloch (BBB) beam splitters exhibit

15% contrast at 24$\hbar k$ splitting, the largest so far ($\hbar k$ is the

photon momentum); single beam splitters achieve 88$\hbar k$. The prospects for

reaching 100s of $\hbar k$ and applications like gravitational wave sensors are

discussed.

\\ ( http://arxiv.org/abs/0903.4192 , 625kb)

------------------------------------------------------------------------------

\\

arXiv:0903.4482

Date: Thu, 26 Mar 2009 11:32:01 GMT (165kb)

Title: An equation of state for low and high energy Bose-Einstein condensation

Authors: Vito Barbarani

Categories: cond-mat.other

Comments: 20 pages, 9 figures. An extended abstract of this work was accepted

for poster contribution at the 22nd General Conference of the Condensed

Matter Division of the European Physical Society (CMD22, August 25th-29th,

2008, Rome)

\\

The aim of this work is to investigate how energy depends on the two-body

interaction potential in Bose-Einstein condensation (BEC) phenomena. An

equation of state is obtained which is valid both for low and high energy BEC,

through the application of a revised form of quantum statistics. An extension

of the singularity conditions describing the state of BEC is given, in order to

consider interactions between particles due to a central interatomic potential.

From the singularity conditions of the corresponding system of hard-sphere

bosons and the equation for the energy of the system in its ground state, the

equation of state connecting temperature, density and energy in BEC is deduced,

with upper and lower limits for the energy depending on the form of the central

interaction potential. It is shown that high energy mode is allowed in the case

of Coulomb type interaction only, low energy mode in the case of non-Coulomb

type interaction. Numerical results are then derived for low energy BEC,

occurring in neutral matter, with application to He-4 and alkali-metal atoms,

and in the case of high energy BEC occurring in systems of charged bosons, with

application to atomic nuclei.

\\ ( http://arxiv.org/abs/0903.4482 , 165kb)

------------------------------------------------------------------------------

\\

arXiv:0903.4674

Date: Thu, 26 Mar 2009 18:59:25 GMT (361kb)

Title: A single structured light beam as an atomic beam splitter

Authors: B. M. Rodriguez-Lara and R. Jauregui

Categories: quant-ph physics.atom-ph

Comments: 10 pages, 5 figures

\\

We propose a scheme to split a cloud of cold non-interacting neutral atoms

based on their dipole interaction with a single structured light beam which

exhibits parabolic cylindrical symmetry. Using semiclassical numerical

simulations, we establish a direct relationship between the general properties

of the light beam and the geometric and kinematic properties acquired by the

atomic cloud as its passes through the beam.

\\ ( http://arxiv.org/abs/0903.4674 , 361kb)

------------------------------------------------------------------------------

The replacements:

------------------------------------------------------------------------------

\\

arXiv:0803.1889

replaced with revised version Mon, 23 Mar 2009 00:47:51 GMT (342kb)

Title: Atom-Pair Tunneling and Quantum Phase Transition in Strong Interaction

Regime

Authors: J.-Q. Liang, J.-L. Liu, W.-D. Li, Z.-J. Li

Categories: cond-mat.other quant-ph

Comments: 6 figures

Journal-ref: Phys. Rev. A 79(3), 033617 (2009) [8 pages]

\\ ( http://arxiv.org/abs/0803.1889 , 342kb)

------------------------------------------------------------------------------

\\

arXiv:0806.1048

replaced with revised version Mon, 23 Mar 2009 21:03:30 GMT (54kb)

Title: Spin squeezing and entanglement

Authors: Geza Toth, Christian Knapp, Otfried G\"uhne, Hans J. Briegel

Categories: quant-ph cond-mat.other cond-mat.stat-mech

Comments: 13 pages including 6 figures and 2 tables, revtex4; v2: changes

before publication in Phys. Rev. A

\\ ( http://arxiv.org/abs/0806.1048 , 54kb)

------------------------------------------------------------------------------

\\

arXiv:cond-mat/0701506

replaced with revised version Thu, 26 Mar 2009 01:21:26 GMT (24kb)

Title: Fractional Spin Hall Effect in Atomic Bose Gases

Authors: Xiong-Jun Liu, Xin Liu, L. C. Kwek and C. H. Oh

Categories: cond-mat.mes-hall quant-ph

Comments: 8 pages, 2 figures, to appear in Phys. Rev. B

\\ ( http://arxiv.org/abs/cond-mat/0701506 , 24kb)

------------------------------------------------------------------------------

\\

arXiv:0804.0286

replaced with revised version Thu, 26 Mar 2009 07:48:06 GMT (442kb,D)

Title: Quasi-condensation and coherence in the quasi-two-dimensional trapped

Bose gas

Authors: R.N. Bisset, M.J. Davis, T.P. Simula, and P.B. Blakie

Categories: cond-mat.other

Comments: 9 pages, 7 figures

\\ ( http://arxiv.org/abs/0804.0286 , 442kb)

------------------------------------------------------------------------------

Till next time,

Matt.

-- ========================================================================= Dr M. J. Davis, Associate Professor in Physics School of Mathematics and Physics, ph : +61 7 334 69824 The University of Queensland, fax : +61 7 336 51242 Brisbane, QLD 4072, mdavis_at_physics.uq.edu.au Australia. www.physics.uq.edu.au/people/mdavis/ ========================================================================= Matt's arXiv selection: weekly summary of cold-atom papers from arXiv.org http://www.physics.uq.edu.au/people/mdavis/matts_arXiv/ ========================================================================= Legal stuff: Unless stated otherwise, this e-mail represents only the views of the sender and not the views of the University of Queensland =========================================================================Received on Thu May 21 2009 - 15:50:53 EST

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