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Related papers: The Stochastic Gross-Pitaevskii Methodology

200 papers

We provide a derivation of a more accurate version of the stochastic Gross-Pitaevskii equation, as introduced by Gardiner et al. (J. Phys. B 35,1555,(2002). The derivation does not rely on the concept of local energy and momentum…

Condensed Matter · Physics 2010-11-02 C. W. Gardiner , M. J. Davis

Fluctuations of the number of condensed atoms in a finite-size, weakly interacting Bose gas confined in a box potential are investigated for temperatures up to the critical region. The canonical partition functions are evaluated using a…

Statistical Mechanics · Physics 2015-05-13 Z. Idziaszek , L. Zawitkowski , M. Gajda , K. Rzazewski

We review phase space techniques based on the Wigner representation that provide an approximate description of dilute ultra-cold Bose gases. In this approach the quantum field evolution can be represented using equations of motion of a…

Statistical Mechanics · Physics 2008-12-04 P. B. Blakie , A. S. Bradley , M. J. Davis , R. J. Ballagh , C. W. Gardiner

A technique to simulate the grand canonical ensembles of interacting Bose gases is presented. Results are generated for many temperatures by averaging over energy-weighted stochastic paths, each corresponding to a solution of coupled…

Soft Condensed Matter · Physics 2009-11-10 P. D. Drummond , P. Deuar , K. V. Kheruntsyan

The dynamics of dark matter-wave solitons in elongated atomic condensates are discussed at finite temperatures. Simulations with the stochastic Gross-Pitaevskii equation reveal a noticeable, experimentally observable spread in individual…

We present a method for solving the stochastic projected Gross-Pitaevskii equation (SPGPE) for a three-dimensional Bose gas in a harmonic-oscillator trapping potential. The SPGPE contains the challenge of both accurately evolving all modes…

Quantum Gases · Physics 2014-01-14 S. J. Rooney , P. B. Blakie , A. S. Bradley

We perform an analysis of the supercooled state in an analogue to an early universe phase transition based on a one dimensional, two-component Bose gas. We demonstrate that the thermal fluctuations in the relative phase between the…

Quantum Gases · Physics 2020-10-28 Thomas P. Billam , Kate Brown , Ian G. Moss

We derive a stochastic process that describes the kinetics of a one-dimensional Bose gas in a regime where three body collisions are important. In this situation the system becomes non integrable offering the possibility to investigate…

Quantum Gases · Physics 2013-05-30 Patrick Navez , Achilleas Lazarides

We apply the Projected Gross-Pitaevskii equation (PGPE) formalism to the experimental problem of the shift in critical temperature $T_c$ of a harmonically confined Bose gas as reported in Gerbier \emph{et al.} [Phys. Rev. Lett. \textbf{92},…

Other Condensed Matter · Physics 2007-06-20 Matthew J. Davis , P. Blair Blakie

A generalised stochastic Gross-Pitaevskii equation describing a partially condensed trapped Bose gas with rotating thermal component is presented. We elucidate the manner in which the rotation changes the role of the high energy cutoff and…

Other Condensed Matter · Physics 2007-05-23 A. S. Bradley , C. W. Gardiner

We propose an efficient stochastic method to implement numerically the Bogolubov approach to study finite-temperature Bose-Einstein condensates. Our method is based on the Wigner representation of the density matrix describing the non…

Statistical Mechanics · Physics 2015-06-24 Alice Sinatra , Yvan Castin , Carlos Lobo

The dynamics of a trapped Bose-condensed gas at finite temperatures is described by a generalized Gross-Pitaevskii equation for the condensate order parameter and a semi-classical kinetic equation for the thermal cloud, solved using…

Statistical Mechanics · Physics 2009-11-07 B. Jackson , E. Zaremba

We study the low-energy collective oscillations of a dilute Bose gas at finite temperature in the collisionless regime. By using a time-dependent mean-field scheme we derive for the dynamics of the condensate and noncondensate components a…

Condensed Matter · Physics 2009-10-31 S. Giorgini

The fluctuating and dissipative dynamics of matter-wave dark solitons within harmonically trapped, partially condensed Bose gases is studied both numerically and analytically. A study of the stochastic Gross-Pitaevskii equation, which…

We show how to adapt the ideas of local energy and momentum conservation in order to derive modifications to the Gross-Pitaevskii equation which can be used phenomenologically to describe irreversible effects in a Bose-Einstein condensate.…

Condensed Matter · Physics 2007-05-23 C. W. Gardiner J. R. Anglin , T. I. A. Fudge

We develop formalism based on the projected Gross Pitaevskii equation to simulate the finite temperature collective mode experiments of Jin et al. [PRL 78, 764 (1997)]. We examine the $m=0$ and $m=2$ quadrupolar modes on the temperature…

Other Condensed Matter · Physics 2009-03-31 A. Bezett , P. B. Blakie

We derive quantum evolution equations for the dynamics of dilute condensed Bose gases. The approach contains, at different orders of approximation, for cases close to equilibrium, the Gross Pitaevskii equation and the first order Hartree…

Condensed Matter · Physics 2007-05-23 Thorsten Koehler , Keith Burnett

We consider a model of a dilute Bose-Einstein condensed gas at finite temperatures, where the condensate coexists in a trap with a cloud of thermal excitations. Within the ZGN formalism, the dynamics of the condensate is described by a…

Statistical Mechanics · Physics 2009-11-07 B. Jackson , E. Zaremba

Describing partially-condensed Bose gases poses a long-standing theoretical challenge. We present exact stochastic Ehrenfest relations for the stochastic projected Gross-Pitaevskii equation, including both number and energy damping…

Quantum Gases · Physics 2020-02-19 Rob G. McDonald , Peter S. Barnett , Fradom Atayee , Ashton S. Bradley

We show that the projected Gross-Pitaevskii equation (PGPE) can be mapped exactly onto Hamilton's equations of motion for classical position and momentum variables. Making use of this mapping, we adapt techniques developed in statistical…

Statistical Mechanics · Physics 2010-11-02 M. J. Davis , S. A. Morgan