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

Date: Mon, 13 Mar 2006 09:17:47 +1000 (EST)

Date: Mon, 13 Mar 2006 09:17:47 +1000 (EST)

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

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Have a good 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/ ------------------------------------------------------------------------- ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603056 Date: Thu, 2 Mar 2006 22:00:44 GMT (22kb) Title: Bose atoms in a trap: a variational Monte Carlo formulation for the universal behavior at the Van der Waals length scale Authors: Imran Khan and Bo Gao Comments: 6 pages, 4 figures Subj-class: Statistical Mechanics \\ We present a variational Monte Carlo (VMC) formulation for the universal equations of state at the Van der Waals length scale [B. Gao, J. Phys. B \textbf{37}, L227 (2004)] for $N$ Bose atoms in a trap. The theory illustrates both how such equations of state can be computed exactly, and the existence and the importance of long-range atom-atom correlation under strong confinement. Explicit numerical results are presented for N=3 and 5, and used to provide a quantitative understanding of the shape-dependent confinement correction that is important for few atoms under strong confinement. \\ ( http://arXiv.org/abs/cond-mat/0603056 , 22kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603059 Date: Fri, 3 Mar 2006 00:44:12 GMT (151kb) Title: Collisions between solitary waves of three-dimensional Bose-Einstein condensates Authors: N.G. Parker, A. M. Martin, S. L. Cornish and C. S. Adams Comments: 5 pages, 4 figures Subj-class: Other \\ We study bright solitary waves of three dimensional trapped Bose-Einstein condensates and their collisions. For a single solitary wave, in addition to an upper critical number, we also find a {\em lower} cut-off, below which no stable state can be found. Collisions between solitary waves can be elastic, inelastic with either reduced or increased outgoing speed, or completely unstable due to a collapse instability. A $\pi$-phase difference between the waves promotes elastic collisions, and gives excellent agreement with recent experimental results over long timescales. \\ ( http://arXiv.org/abs/cond-mat/0603059 , 151kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603070 Date: Fri, 3 Mar 2006 10:51:43 GMT (260kb) Title: Dark solitons in F=1 spinor Bose--Einstein condensate Authors: Masaru Uchiyama, Jun'ichi Ieda, Miki Wadati Comments: 19 pages, 3 figures Subj-class: Other; Soft Condensed Matter \\ We study dark soliton solutions of a multi-component Gross--Pitaevskii equation for hyperfine spin F=1 spinor Bose--Einstein condensate. The interactions are supposed to be inter-atomic repulsive and anti-ferromagnetic ones of equal magnitude. The solutions are obtained from those of an integrable $2\times 2$ matrix nonlinear Schr\"{o}dinger equation with nonvanishing boundary conditions. We investigate the one-soliton and two-soliton solutions in detail. One-soliton is classified into two kinds. The ferromagnetic state has wavefunctions of domain-wall shape and its total spin is nonzero. The polar state provides a hole soliton and its total spin is zero. These two states are selected by choosing the type of the boundary conditions. In two-soliton collisions, we observe the spin-mixing or spin-transfer. It is found that, as "magnetic" carriers, solitons in the ferromagnetic state are operative for the spin-mixing while those in the polar are passive. \\ ( http://arXiv.org/abs/cond-mat/0603070 , 260kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603071 Date: Fri, 3 Mar 2006 10:03:49 GMT (5kb) Title: Generalized Thermostatistics and Bose-Einstein Condensation Authors: H. G. Miller, F. C. Khanna, R.Teshima, A.R. Plastino and A. Plastino Subj-class: Statistical Mechanics \\ Analytical expressions for Bose-Einstein condensation of an ideal Bose gas analyzed within the strictures of non-extensive, generalized thermostatistics are here obtained. \\ ( http://arXiv.org/abs/cond-mat/0603071 , 5kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603082 Date: Fri, 3 Mar 2006 16:15:48 GMT (2921kb) Title: Liquid 4He: contributions to first principles theory of quantized vortices, thermohydrodynamic properties, and the lambda transition Authors: H.W. Jackson Comments: 155 pages, 28 figures Subj-class: Statistical Mechanics \\ Liquid 4He has been studied extensively for almost a century, but there are still a number of outstanding weak or missing links in our comprehension of it. This paper reviews some of the principal paths taken in previous research and then proceeds to fill gaps and create an integrated picture with more complete understanding through first principles treatment of a realistic model that starts with a microscopic, atomistic description of the liquid. Newly derived results for vortex cores and thermohydrodynamic properties for a two-fluid model are used to show that interacting quantized vortices may produce a lambda anomaly in specific heat near the superfluid transition where flow properties change. The nature of the order in the superfluid state is explained. Experimental support for new calculations is exhibited, and a unique specific heat experiment is proposed to test predictions of the theory. Relevance of the theory to modern research in cosmology, astrophysics, and Bose-Einstein condensates is discussed. \\ ( http://arXiv.org/abs/cond-mat/0603082 , 2921kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603083 Date: Fri, 3 Mar 2006 16:39:15 GMT (38kb) Title: Spin Hall Effect in Atoms Authors: Xiong-Jun Liu, Xin Liu, L. C. Kwek, and C. H. Oh Comments: 4 pages, 1 figure Subj-class: Mesoscopic Systems and Quantum Hall Effect \\ We investigate a new type of spin hall effect (SHE) in neutral atomic system by coupling atoms' internal freedom (atom spin states) to radiation. Atoms with opposite spin polarization are shown to experience opposite effective electromagnetic fields, and then can move in the opposite direction. For this pure spin currents in atomic system are obtained, i.e. no massive current occurs in this way. Besides, we show for special case the spin currents created in present way can exhibit interesting topological properties. \\ ( http://arXiv.org/abs/cond-mat/0603083 , 38kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0511206 replaced with revised version Thu, 2 Mar 2006 21:18:59 GMT (21kb) Title: Solitons of Bose-Fermi mixtures in a strongly elongated trap Authors: J. Santhanam, V. M. Kenkre, V. V. Konotop Comments: 1 figure Subj-class: Other Journal-ref: Physical Review A, Volume 73, Number 1, 013612 (2006) \\ ( http://arXiv.org/abs/cond-mat/0511206 , 21kb) ------------------------------------------------------------------------------ \\ Paper: quant-ph/0603025 Date: Fri, 3 Mar 2006 13:43:32 GMT (661kb) Title: Intensity correlation and anticorrelations in coherently prepared atomic vapor Authors: Gombojav O. Ariunbold, Vladimir A. Sautenkov, Yuri V. Rostovtsev, and Marlan O. Scully \\ Motivated by the recent experiment [V.A. Sautenkov, Yu.V. Rostovtsev, and M.O. Scully, Phys. Rev. A 72, 065801 (2005)], we develop a theoretical model in which the field intensity fluctuations resulted from resonant interaction of a dense atomic medium with laser field having finite bandwidth. The intensity-intensity cross correlation between two circular polarized beams can be controlled by the applied external magnetic field. A smooth transition from perfect correlations to anti-correlations (at zero delay time) of the outgoing beams as a function of the magnetic field strength is observed. It provides us with the desired information about decoherence rate in, for example, $^{87}$Rb atomic vapor. \\ ( http://arXiv.org/abs/quant-ph/0603025 , 661kb) ------------------------------------------------------------------------------ \\ Paper: quant-ph/0603028 Date: Fri, 3 Mar 2006 17:33:37 GMT (291kb) Title: Simultaneous Magneto-Optical Trapping of Bosonic and Fermionic Chromium Atoms Authors: R. Chicireanu, A. Pouderous, R. Barbe, B. Laburthe-Tolra, E. Marechal, L. Vernac, J.-C. Keller, and O. Gorceix Comments: 8 pages, 5 figures. submitted to Phys Rev A \\ We report on magneto-optical trapping of fermionic 53Cr atoms. A Zeeman-slowed atomic beam provides loading rates up to 3 10^6 /s. We present systematic characterization of the magneto-optical trap (MOT). We obtain up to 5 10^5 atoms in the steady state MOT. The atoms radiatively decay from the excited P state into metastable D states, and, due to the large dipolar magnetic moment of chromium atoms in these states, they can remain magnetically trapped in the quadrupole field gradient of the MOT. We study the accumulation of metastable 53Cr atoms into this magnetic trap. We also report on the first simultaneous magneto-optical trapping of bosonic 52Cr and fermionic 53Cr atoms. Finally, we characterize the light assisted collision losses in this Bose-Fermi cold mixture. \\ ( http://arXiv.org/abs/quant-ph/0603028 , 291kb) ------------------------------------------------------------------------------ \\ Paper: physics/0512084 replaced with revised version Thu, 2 Mar 2006 01:36:45 GMT (81kb) Title: Direct excitation of the forbidden clock transition in neutral 174Yb atoms confined to an optical lattice Authors: Zeb W. Barber (1), Chad W. Hoyt (1), Chris W. Oates (1), Leo Hollberg (1), Aleksei V. Taichenachev (2), Valera I. Yudin (2) ((1) NIST-Boulder, (2) Novosibirsk) Comments: Submitted to Physics Review Letters Subj-class: Atomic Physics \\ ( http://arXiv.org/abs/physics/0512084 , 81kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603091 Date: Sat, 4 Mar 2006 17:51:02 GMT (64kb) Title: Fermion pairing with population imbalance: energy landscape and phase separation in a constrained Hilbert subspace Authors: Zheng-Cheng Gu, Geoff Warner and Fei Zhou (UBC) Comments: 4 pages, 3 figures Subj-class: Other \\ In this Letter we map out the mean field energy potential landscape of fermion pairing states with population imbalance near broad Feshbach Resonances. We apply the landscape to investigate the nature of phase separation, when the Hilbert space is subject to the constraint of constant population imbalance. We calculate the scattering length dependence of the critical population imbalance for various phase separated states across Feshbach resonances. \\ ( http://arXiv.org/abs/cond-mat/0603091 , 64kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603093 Date: Sat, 4 Mar 2006 05:14:32 GMT (179kb) Title: The q-deformed Bose gas: Integrability and thermodynamics Authors: Michael Bortz and Sergey Sergeev Comments: 10 pages, 6 figures Subj-class: Statistical Mechanics \\ We investigate the exact solution of the q-deformed one-dimensional Bose gas to derive all integrals of motion and their corresponding eigenvalues. As an application, the thermodynamics is given and compared to an effective field theory at low temperatures. \\ ( http://arXiv.org/abs/cond-mat/0603093 , 179kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603094 Date: Sat, 4 Mar 2006 07:06:54 GMT (104kb) Title: Electromagnetically induced transparency in an atom-molecule Bose-Einstein condensate Authors: Guang-Ri Jin, Chul Koo Kim, and Kyun Nahm Comments: 3.7pages, 4 figures Subj-class: Other \\ We propose a new measurement scheme for the atom-molecule dark state by using electromagnetically induced transparency (EIT) technique. Based on a density-matrix formalism, we calculate the absorption coefficient numerically. The appearance of the EIT dip in the spectra profile gives clear evidence for the creation of the dark state in the atom-molecule Bose-Einstein condensate. \\ ( http://arXiv.org/abs/cond-mat/0603094 , 104kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603106 Date: Sun, 5 Mar 2006 18:21:53 GMT (124kb) Title: Kinetics of quantum fluctuations in the Bose-Einstein condensation of polaritons Authors: Davide Sarchi, Vincenzo Savona Subj-class: Materials Science; Mesoscopic Systems and Quantum Hall Effect; Other \\ We develop a kinetic theory of polariton non-equilibrium Bose-Einstein condensation, in which the field dynamics of collective excitations is treated self-consistently along with the condensation kinetics. The theory accounts properly for the dominant role of quantum fluctuations in the condensate. In realistic situations with optical excitation at high energy, it predicts a considerable depletion of the condensate caused by long-wavelength fluctuations. We discuss how this depletion and the subsequent partial suppression of long-range order depend on the finite size of the system. \\ ( http://arXiv.org/abs/cond-mat/0603106 , 124kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603113 Date: Mon, 6 Mar 2006 03:14:21 GMT (27kb) Title: Stability analysis for $n$-component Bose-Einstein condensate Authors: David C. Roberts and Masahito Ueda Subj-class: Other; Statistical Mechanics \\ We derive the dynamic and thermodynamic stability conditions for dilute multicomponent Bose-Einstein condensates (BECs). These stability conditions, generalized for $n$-component BECs, are found to be equivalent and are shown to be consistent with the phase diagrams of two- and three-component condensates that are derived from energetic arguments. \\ ( http://arXiv.org/abs/cond-mat/0603113 , 27kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603118 Date: Mon, 6 Mar 2006 15:06:36 GMT (258kb) Title: Interacting Fermi Gases in Disordered One-Dimensional Lattices Authors: Gao Xianlong, M. Polini, B. Tanatar, and M.P. Tosi Comments: 7 pages, 4 figures, submitted Subj-class: Strongly Correlated Electrons; Disordered Systems and Neural Networks \\ Interacting two-component Fermi gases loaded in a one-dimensional (1D) lattice and subject to harmonic trapping exhibit intriguing compound phases in which fluid regions coexist with local Mott-insulator and/or band-insulator regions. Motivated by experiments on cold atoms inside disordered optical lattices, we present a theoretical study of the effects of a random potential on these ground-state phases. Within a density-functional scheme we show that disorder has two main effects: (i) it destroys the local insulating regions if it is sufficiently strong compared with the on-site atom-atom repulsion, and (ii) it induces an anomaly in the compressibility at low density from quenching of percolation. \\ ( http://arXiv.org/abs/cond-mat/0603118 , 258kb) ------------------------------------------------------------------------------ \\ Paper (*cross-listing*): nlin.SI/0603010 Date: Fri, 3 Mar 2006 10:54:11 GMT (25kb) Title: Inverse scattering method for the multicomponent nonlinear Schr\"odinger equation under nonvanishing boundary conditions Authors: Jun'ichi Ieda, Masaru Uchiyama, Miki Wadati Comments: 22 pages, 2 figures Subj-class: Exactly Solvable and Integrable Systems; Mathematical Physics; Other \\ Matrix generalization of the inverse scattering method is developed to solve the multicomponent nonlinear Schr\"odinger equation with nonvanishing boundary conditions. It is shown that the initial value problem can be solved exactly. The multi-soliton solution is obtained from the Gel'fand--Levitan--Marchenko equation. \\ ( http://arXiv.org/abs/nlin/0603010 , 25kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0509505 replaced with revised version Mon, 6 Mar 2006 03:38:56 GMT (232kb) Title: Quantum atom optics with fermions from molecular dissociation Authors: K. V. Kheruntsyan Comments: Changes in response to referees' comments, updated references Subj-class: Other; Statistical Mechanics \\ ( http://arXiv.org/abs/cond-mat/0509505 , 232kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0510397 replaced with revised version Mon, 6 Mar 2006 08:56:27 GMT (81kb) Title: Observations of density fluctuations in an elongated Bose gas: ideal gas and quasi-condensate regimes Authors: Jerome Esteve (LCFIO), Jean-Baptiste Trebbia (LCFIO), Thorsten Schumm (LCFIO), Alain Aspect (LCFIO), Christoph I. Westbrook (LCFIO), Isabelle Bouchoule (LCFIO) Proxy: ccsd ccsd-00011123 Subj-class: Other \\ ( http://arXiv.org/abs/cond-mat/0510397 , 81kb) ------------------------------------------------------------------------------ \\ Paper: quant-ph/0603037 Date: Mon, 6 Mar 2006 07:05:49 GMT (19kb) Title: Bright entanglement in the intracavity nonlinear coupler Authors: M.K. Olsen Comments: 15 pages, 4 figures \\ We show that the intracavity Kerr nonlinear coupler is a potential source of bright continuous variable entangled light beams which are tunable and spatially separated. This system may be realised with integrated optics and thus provides a potentially rugged and stable source of bright entangled beams. \\ ( http://arXiv.org/abs/quant-ph/0603037 , 19kb) ------------------------------------------------------------------------------ \\ Paper: quant-ph/0603039 Date: Mon, 6 Mar 2006 10:38:52 GMT (164kb) Title: Effects of cavity-field statistics on atomic entanglement Authors: Biplab Ghosh, A. S. Majumdar, N. Nayak Comments: Revtex, 9 pages, 10 eps figures \\ We study the entanglement properties of a pair of two-level atoms going through a cavity one after another. The initial joint state of two successive atoms that enter the cavity is unentangled. Interactions mediated by the cavity photon field result in the final two-atom state being of a mixed entangled type. We consider respectively various field statistics as in the Fock state field, thermal field, coherent state field and squeezed state field inside the cavity, and calculate the entanglement of formation, the well-known measure appropriate for mixed states, of the joint two-atom state as a function of the Rabi-angle $gt$. We present a detailed and comparitive study of two-atom entanglement for low and high mean photon number cases corresponding to the different cavity fields. \\ ( http://arXiv.org/abs/quant-ph/0603039 , 164kb) ------------------------------------------------------------------------------ \\ Paper: quant-ph/0603044 Date: Mon, 6 Mar 2006 15:43:26 GMT (152kb) Title: Optical Transparency Using Interference Between Two Modes of a Cavity Authors: J.D. Franson and S.M. Hendrickson Comments: 4 pages, 5 figures \\ In electromagnetically-induced transparency (EIT), the absorption of a probe beam is greatly reduced due to destructive interference between two dressed atomic states produced by a strong laser beam. Here we show that a similar reduction in the single-photon absorption rate can be achieved by tuning a probe beam to be halfway between the resonant frequencies of two modes of a cavity. This technique is expected to be useful in enhancing two-photon absorption while reducing losses due to single-photon scattering. \\ ( http://arXiv.org/abs/quant-ph/0603044 , 152kb) ------------------------------------------------------------------------------ \\ Paper: quant-ph/0603048 Date: Mon, 6 Mar 2006 18:58:42 GMT (90kb) Title: Experimental interference of independent photons Authors: Rainer Kaltenbaek, Bibiane Blauensteiner, Marek Zukowski, Markus Aspelmeyer, Anton Zeilinger Comments: 4 pages, 3 figures \\ Interference of photons emerging from independent sources is essential for modern quantum information processing schemes, above all quantum repeaters and linear-optics quantum computers. We report an observation of non-classical interference of two single photons originating from two independent, separated sources, which were actively synchronized with an r.m.s. timing jitter of 260 fs. The resulting (two-photon) interference visibility was 83(+/-)4 %. \\ ( http://arXiv.org/abs/quant-ph/0603048 , 90kb) ------------------------------------------------------------------------------ \\ Paper: quant-ph/0603054 Date: Tue, 7 Mar 2006 16:08:59 GMT (193kb) Title: Elastic vs. inelastic coherent backscattering of laser light by cold atoms: a master equation treatment Authors: Vyacheslav Shatokhin, Cord A. M\"uller, Andreas Buchleitner Comments: 14 pages, 6 figures \\ We give a detailed derivation of the master equation description of the coherent backscattering of laser light by cold atoms. In particular, our formalism accounts for the nonperturbative nonlinear response of the atoms when the injected intensity saturates the atomic transition. Explicit expressions are given for total and elastic backscattering intensities in the different polarization channels, for the simplest nontrivial multiple scattering scenario of intense laser light multiply scattering from two randomly placed atoms. \\ ( http://arXiv.org/abs/quant-ph/0603054 , 193kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603162 Date: Tue, 7 Mar 2006 12:25:25 GMT (152kb) Title: Bose-Fermi mixtures in an optical lattice Authors: K. Sengupta, N. Dupuis, and P. Majumdar Comments: 10 pages, 7 figures, version 1 Subj-class: Strongly Correlated Electrons \\ We study an atomic Bose-Fermi mixture in an optical lattice which is confined using an optical trap. We obtain the Mott ground states of such a system in the limit of deep optical lattice and discuss the effect of quantum fluctuations on these states. We also study the superfluid-insulator transitions of bosons and metal-insulator transition of fermions in such a mixture within a slave-rotor mean-field approximation, and obtain the corresponding phase diagram. We discuss experimental implications of our results. \\ ( http://arXiv.org/abs/cond-mat/0603162 , 152kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0410417 replaced with revised version Tue, 7 Mar 2006 09:20:21 GMT (544kb) Title: Universality in Few-body Systems with Large Scattering Length Authors: Eric Braaten (Ohio State U.), H.-W. Hammer (INT and Bonn U.) Comments: 219 pages, 58 figures, accepted for publication in Physics Reports, updated and some errors corrected Report-no: INT-PUB 04-27, HISKP-TH-06-07 Subj-class: Other; Soft Condensed Matter \\ ( http://arXiv.org/abs/cond-mat/0410417 , 544kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0510680 replaced with revised version Tue, 7 Mar 2006 17:21:49 GMT (71kb) Title: Response of a Fermi gas to time-dependent perturbations: Riemann-Hilbert approach at non-zero temperatures Authors: Bernd Braunecker Comments: 10 pages, 2 figures; 2 appendices added, a few modifications in the text, typos corrected; published in Phys. Rev. B Subj-class: Strongly Correlated Electrons; Mesoscopic Systems and Quantum Hall Effect Journal-ref: Phys. Rev. B 73, 075122 (2006) DOI: 10.1103/PhysRevB.73.075122 \\ ( http://arXiv.org/abs/cond-mat/0510680 , 71kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603190 Date: Wed, 8 Mar 2006 03:49:58 GMT (18kb) Title: Realization, Characterization, and Detection of Novel Superfluid Phases with Pairing between Unbalanced Fermion Species Authors: Kun Yang Comments: This is an invited contribution to a book titled "Pairing beyond BCS Theory in Fermionic Systems" (Mark Alford, John Clark and Armen Sedrakian, eds.), to be published by World Scientific. 20 pages Subj-class: Superconductivity \\ In this chapter we review recent experimental and theoretical work on various novel superfluid phases in fermion systems, that result from pairing fermions of different species with unequal densities. After briefly reviewing existing experimental work in superconductors subject to a strong magnetic field and trapped cold fermionic atom systems, we discuss how to characterize the possible pairing phases based on their symmetry properties, and the structure/topology of the Fermi surface(s) formed by the unpaired fermions due to the density imbalance. We also discuss possible experimental probes that can be used to directly detect the structure of the superfluid order parameter in superconductors and trapped cold atom systems, which may establish the presence of some of these phases unambiguously. \\ ( http://arXiv.org/abs/cond-mat/0603190 , 18kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603197 Date: Wed, 8 Mar 2006 09:54:48 GMT (613kb) Title: Dark solitons as quasiparticles in trapped condensates Authors: V.A. Brazhnyi, V.V. Konotop, L.P. Pitaevskii Comments: 16 pages, 4 figures. To appear in Phys. Rev. A Subj-class: Other \\ We present a theory of dark soliton dynamics in trapped quasi-one-dimensional Bose-Einstein condensates, which is based on the local density approximation. The approach is applicable for arbitrary polynomial nonlinearities of the mean-field equation governing the system as well as to arbitrary polynomial traps. In particular, we derive a general formula for the frequency of the soliton oscillations in confining potentials. A special attention is dedicated to the study of the soliton dynamics in adiabatically varying traps. It is shown that the dependence of the amplitude of oscillations {\it vs} the trap frequency (strength) is given by the scaling law $X_0\propto\omega^{-\gamma}$ where the exponent $\gamma$ depends on the type of the two-body interactions, on the exponent of the polynomial confining potential, on the density of the condensate and on the initial soliton velocity. Analytical results obtained within the framework of the local density approximation are compared with the direct numerical simulations of the dynamics, showing remarkable match. Various limiting cases are addressed. In particular for the slow solitons we computed a general formula for the effective mass and for the frequency of oscillations. \\ ( http://arXiv.org/abs/cond-mat/0603197 , 613kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603200 Date: Wed, 8 Mar 2006 11:37:19 GMT (610kb) Title: Ordered structures in rotating ultracold Bose gases Authors: N.Barberan, M.Lewenstein, K.Osterloh, and D.Dagnino Comments: 35 pages, 17 figures Subj-class: Mesoscopic Systems and Quantum Hall Effect \\ The characterization of small samples of cold bosonic atoms in rotating microtraps has recently attracted increasing interest due to the possibility to deal with a few number of particles per site in optical lattices. We analyze the evolution of ground state structures as the rotational frequency $\Omega$ increases. Various kinds of ordered structures are observed. For $N<10$ atoms, the standard scenario, valid for large sytems, is absent, and only gradually recovered as $N$ increases. The vortex contribution to the total angular momentum $L$ as a function of $\Omega$ ceases to be an increasing function of $\Omega$, as observed in experiments of Chevy {\it et al.} (Phys. Rev. Lett. 85, 2223 (2000)). Instead, for small $N$, it exhibits a sequence of peaks showing wide minima at the values of $\Omega$, where no vortices appear. \\ ( http://arXiv.org/abs/cond-mat/0603200 , 610kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603204 Date: Wed, 8 Mar 2006 13:56:07 GMT (94kb) Title: Quantum Dynamics of Atomic Coherence in a Spin-1 Condensate: Mean-Field versus Many-Body Simulation Authors: L.I.Plimak, C.Wei\ss, R.Walser, and W.P.Schleich Comments: Accepted for publication for the special issue of "Optics Communications" on Quantum Control of Light and Matter Subj-class: Other \\ We analyse and numerically simulate the full many-body quantum dynamics of a spin-1 condensate in the single spatial mode approximation. Initially, the condensate is in a ``ferromagnetic'' state with all spins aligned along the $y$ axis and the magnetic field pointing along the z axis. In the course of evolution the spinor condensate undergoes a characteristic change of symmetry, which in a real experiment could be a signature of spin-mixing many-body interactions. The results of our simulations are conveniently visualised within the picture of irreducible tensor operators. \\ ( http://arXiv.org/abs/cond-mat/0603204 , 94kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603212 Date: Wed, 8 Mar 2006 15:58:26 GMT (131kb) Title: General variational many-body theory with complete self-consistency for trapped bosonic systems Authors: Alexej I. Streltsov, Ofir E. Alon and Lorenz S. Cederbaum Comments: 53 pages, 8 figures Subj-class: Other \\ In this work we develop a complete variational many-body theory for a system of $N$ trapped bosons interacting via a general two-body potential. In this theory both the many-body basis functions {\em and} the respective expansion coefficients are treated as variational parameters. The optimal variational parameters are obtained {\em self-consistently} by solving a coupled system of non-eigenvalue -- generally integro-differential -- equations to get the one-particle functions and by diagonalizing the secular matrix problem to find the expansion coefficients. We call this theory multi-configurational Hartree for bosons or MCHB(M), where M specifies explicitly the number of one-particle functions used to construct the configurations. General rules for evaluating the matrix elements of one- and two-particle operators are derived and applied to construct the secular Hamiltonian matrix. We discuss properties of the derived equations. It is demonstrated that for any practical computation where the configurational space is restricted, the description of trapped bosonic systems strongly depends on the choice of the many-body basis set used, i.e., self-consistency is of great relevance. As illustrative examples we consider bosonic systems trapped in one- and two-dimensional symmetric and asymmetric double-well potentials. We demonstrate that self-consistency has great impact on the predicted physical properties of the ground and excited states and show that the lack of self-consistency may lead to physically wrong predictions. The convergence of the general MCHB(M) scheme with a growing number M is validated in a specific case of two bosons trapped in a symmetric double-well. \\ ( http://arXiv.org/abs/cond-mat/0603212 , 131kb) ------------------------------------------------------------------------------ \\ Paper: quant-ph/0603063 Date: Wed, 8 Mar 2006 09:50:25 GMT (176kb) Title: Matter-wave diffraction in time with a linear potential Authors: A. del Campo, J. G. Muga Comments: 11 pages, 6 figures \\ Diffraction in time of matter waves incident on a shutter which is removed at time $t=0$ is studied in the presence of a linear potential. The solution is also discussed in phase space in terms of the Wigner function. An alternative configuration relevant to current experiments where particles are released from a hard wall trap is also analyzed for single-particle states and for a Tonks-Girardeau gas. \\ ( http://arXiv.org/abs/quant-ph/0603063 , 176kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603264 Date: Thu, 9 Mar 2006 19:39:10 GMT (24kb) Title: BCS-BEC crossover and quantum phase transition for 6Li and 40K atoms across Feshbach resonance Authors: W. Yi and L.-M. Duan Comments: 7 pages, 6 figures Subj-class: Other \\ We systematically study the BCS-BEC crossover and the quantum phase transition in ultracold 6Li and 40K atoms across a wide Feshbach resonance. The background scattering lengths for 6Li and 40K have opposite signs, which lead to very different behaviors for these two types of atoms. For 40K, both the two-body and the many-body calculations show that the system always has two branches of solutions: one corresponds to a deeply bound molecule state; and the other, the one accessed by the current experiments, corresponds to a weakly bound state with population always dominantly in the open channel. For 6Li, there is only a unique solution with the standard crossover from the weakly bound Cooper pairs to the deeply bound molecules as one sweeps the magnetic field through the crossover region. Because of this difference, for the experimentally accessible state of 40K, there is a quantum phase transition at zero temperature from the superfluid to the normal fermi gas at the positive detuning of the magnetic field where the s-wave scattering length passes its zero point. For 6Li, however, the system changes continuously across the zero point of the scattering length. For both types of atoms, we also give detailed comparison between the results from the two-channel and the single-channel model over the whole region of the magnetic field detuning. \\ ( http://arXiv.org/abs/cond-mat/0603264 , 24kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0603270 Date: Thu, 9 Mar 2006 20:52:35 GMT (844kb) Title: Dressed-molecules in resonantly-interacting ultracold atomic Fermi gases Authors: G.M. Falco, H.T.C. Stoof Comments: 44 pages, 24 figures Subj-class: Other; Superconductivity \\ We present a detailed analysis of the two-channel atom-molecule effective Hamiltonian for an ultracold two-component homogeneous Fermi gas interacting near a Feshbach resonance. We particularly focus on the two-body and many-body properties of the dressed molecules in such a gas. An exact result for the many-body T-matrix of the two-channel theory is derived by both considering coupled vertex equations and the functional integral methods. The field theory incorporates exactly the two-body physics of the Feshbach scattering by means of simple analytical formulas without any fitting parameters. New interesting many-body effects are discussed in the case of narrow resonances. We give also a description of the BEC-BCS crossover above and below T_C. The effects of different approximations for the selfenergy of the dressed molecules are discussed. The single-channel results are derived as a special limit for broad resonances. Moreover, through an analytic analysis of the BEC limit, the relation between the composite boson of the single-channel model and the dressed-molecule of the two-channel model is established. \\ ( http://arXiv.org/abs/cond-mat/0603270 , 844kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0510567 replaced with revised version Thu, 9 Mar 2006 09:33:45 GMT (502kb) Title: Thermometry of Fermionic Atoms in an Optical Lattice Authors: Michael K\"ohl Comments: 4 pages Subj-class: Strongly Correlated Electrons Journal-ref: Phys. Rev. A 73, 031601(R) (2006) DOI: 10.1103/PhysRevA.73.031601 \\ ( http://arXiv.org/abs/cond-mat/0510567 , 502kb) ------------------------------------------------------------------------------ \\ Paper: cond-mat/0511080 replaced with revised version Thu, 9 Mar 2006 11:58:43 GMT (282kb) Title: Probing number squeezing of ultracold atoms across the superfluid-Mott insulator transition Authors: Fabrice Gerbier, Simon Foelling, Artur Widera, Olaf Mandel, Immanuel Bloch Comments: 4 pages; 4 figures Subj-class: Other Journal-ref: Phys. Rev. Lett. 96, 090401 (2006) \\ ( http://arXiv.org/abs/cond-mat/0511080 , 282kb) ------------------------------------------------------------------------------Received on Mon Mar 13 2006 - 09:17:47 EST

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