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Related papers: Atomic Gases at Negative Kinetic Temperature

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We propose a method to experimentally measure the internal energy of a system of ultracold atoms trapped in optical lattices by coupling them to the fields of two optical cavities. We show that the tunnelling and self-interaction terms of…

Quantum Physics · Physics 2018-01-08 Louis Villa , Gabriele De Chiara

The ability to trap and to manipulate individual atoms is at the heart of current implementations of quantum simulations, quantum computing, and long-distance quantum communication. Controlling the motion of larger particles opens up yet…

We present a scheme to cool the motional state of neutral atoms confined in sites of an optical lattice by immersing the system in a superfluid. The motion of the atoms is damped by the generation of excitations in the superfluid, and under…

Quantum Physics · Physics 2009-09-29 A. J. Daley , P. O. Fedichev , P. Zoller

Ultra-cold atoms in optical lattices realize simple, fundamental models in condensed matter physics. Our 87Rb Bose-Einstein condensate is confined in a harmonic trapping potential to which we add an optical lattice potential. Here we…

Quantum Gases · Physics 2010-09-15 K. Jimenez-Garcia , R. L. Compton , Y. -J. Lin , W. D. Phillips , J. V. Porto , I. B. Spielman

Motivated by recent experiments and theoretical investigations on binary mixtures, we investigate the miscible-immiscible transition at finite temperature by means of Quantum Monte Carlo. Based on the observation that the segregated phase…

Quantum Gases · Physics 2018-03-16 F. Lingua , B. Capogrosso-Sansone , F. Minardi , V. Penna

At present, there is considerable interest in using atomic fermions in optical lattices to emulate the mathematical models that have been used to study strongly correlated electronic systems. Some of these models, such as the two…

Quantum Gases · Physics 2015-05-13 Tin-Lun Ho , Qi Zhou

We demonstrate that a Kalman filter applied to estimate the position of an optically levitated nanoparticle, and operated in real-time within a Field Programmable Gate Array (FPGA), is sufficient to perform closed-loop parametric feedback…

Quantum Physics · Physics 2018-04-16 Ashley Setter , Marko Toroš , Jason F. Ralph , Hendrik Ulbricht

We study the sympathetic cooling of a trapped Fermi gas interacting with an ideal Bose gas below the critical temperature of the Bose-Einstein condensation. We derive the quantum master equation, which describes the dynamics of the…

Soft Condensed Matter · Physics 2009-11-11 Z. Idziaszek , L. Santos , M. Lewenstein

The pursuit of high optical depth and long coherence time in atomic ensembles faces a fundamental thermodynamic constraint: heating enhances light-atom coupling via increased density but degrades coherence through thermal broadening, while…

Atomic Physics · Physics 2025-05-06 Changhao Cheng , Jinxian Guo

We construct a fully self-consistent non-equilibrium theory for the dynamics of two interacting finite-temperature atomic Bose-Einstein condensates. The condensates are described by dissipative Gross-Pitaevskii equations, coupled to quantum…

Quantum Gases · Physics 2015-01-15 M. J. Edmonds , K. L. Lee , N. P. Proukakis

We demonstrate the possibility of three-dimensional cooling of neutral atoms by illuminating them with two counterpropagating laser beams of mutually orthogonal linear polarization, where one of the lasers is a speckle field, i.e. a highly…

Atomic Physics · Physics 2009-10-31 Peter Horak , Jean-Yves Courtois , Gilbert Grynberg

We study the dynamics of the cooling of a gas of caesium atoms in an optical lattice, both experimentally and with 1D full-quantum Monte Carlo simulations. We find that, contrary to the standard interpretation of the Sisyphus model, the…

Atomic Physics · Physics 2007-05-23 Claude M. Dion , Peder Sjolund , Stefan J. H. Petra , Svante Jonsell , Anders Kastberg

A simple and computationally efficient algorithm enables implementing negative temperature values in a spin dynamics simulation. The algorithm uses a Langevin spin dynamics thermostat with a negative damping parameter, enabling the…

Materials Science · Physics 2024-03-05 Pui-Wai Ma , Sergei L. Dudarev

E.A. Schoene et al., in arXiv:1012.3207 [Phys. Rev.A, 82, 023419 (2010)] give incorrect interpretation of their experimental results. Really we observe a temporary capture and additional cooling of atoms in the presence of the orthogonal…

General Physics · Physics 2011-01-13 V. A. Kuz'menko

A grand-canonical system of interacting bosons is considered to study phase transitions of ultracold atoms in an optical lattice. The phase diagram is discussed in terms of a matrix-like order parameter, representing a symmetric phase (Mott…

Statistical Mechanics · Physics 2007-05-23 K. Ziegler

We study the evaporative cooling of magnetically trapped atomic hydrogen on the basis of the kinetic theory of a Bose gas. The dynamics of trapped atoms is described by the coupled differential equations, considering both the evaporation…

Statistical Mechanics · Physics 2009-10-31 Makoto Yamashita , Masato Koashi , Tetsuya Mukai , Masaharu Mitsunaga , Nobuyuki Imoto

Demonstrating that despite loss processes, Bose-Einstein condensates can be formed in steady state is a prerequisite for obtaining a coherent beam of atoms in a continuous-wave atom laser. In this paper we propose a method for loading atoms…

Quantum Physics · Physics 2009-11-06 Satyan Bhongale , Murray Holland

We study the phase transition of a gas of Rb atoms to quantum degeneracy in the combined potential of a harmonically confining magnetic trap and the periodic potential of an optical lattice. For high optical lattice potentials we observe a…

Condensed Matter · Physics 2009-05-28 S. Burger , F. S. Cataliotti , C. Fort , P. Maddaloni , F. Minardi , M. Inguscio

We study the optimization of evaporative cooling in trapped bosonic atoms on the basis of quantum kinetic theory of a Bose gas. The optimized cooling trajectory for $^{87}$Rb atoms indicates that the acceleration of evaporative cooling…

Statistical Mechanics · Physics 2009-11-07 Makoto Yamashita , Masato Koashi , Tetsuya Mukai , Masaharu Mitsunaga , Nobuyuki Imoto , Takaaki Mukai

We study a composite photon-Bose condensed atoms (BEC) system in an optical lattice confined in a cavity. We show that the system is able to produce an effective photon-photon repulsion in the presence of an external pump. We predict for…

Statistical Mechanics · Physics 2008-10-22 Aranya B. Bhattacherjee , ManMohan
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