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Related papers: C-Field Methods for Non-Equilibrium Bose Gases

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The dynamics of a two-component dilute Bose gas of atoms at zero temperature is described in the mean field approximation by a two-component Gross-Pitaevskii Equation. We solve this equation assuming a Gaussian shape for the wavefunction,…

Condensed Matter · Physics 2016-08-31 Th. Busch , J. I. Cirac , V. M. Perez-Garcia , P. Zoller

We present a theory for the linear dynamics of a weakly interacting Bose gas confined inside a harmonic trap at finite temperature. The theory treats the motions of the condensate and of the non-condensate on an equal footing within a…

Statistical Mechanics · Physics 2007-05-23 Xia-Ji Liu , Hui Hu , A. Minguzzi , M. P. Tosi

We present a simulation scheme for discrete-velocity gases based on {\em local thermodynamic equilibrium}. Exploiting the kinetic nature of discrete-velocity gases, in that context, results in a natural splitting of fluxes, and the…

comp-gas · Physics 2008-02-03 Balu Nadiga , Dale Pullin

In this paper, we propose an efficient and accurate numerical method for computing the dynamics of rotating two-component Bose--Einstein condensates (BECs) which is described by coupled Gross--Pitaevskii equations (CGPEs) with an angular…

Numerical Analysis · Mathematics 2013-06-10 Ming Ju , Qinglin Tang , Yanzhi Zhang

While the Gross--Pitaevskii equation is well-established as the canonical dynamical description of atomic Bose-Einstein condensates (BECs) at zero-temperature, describing the dynamics of BECs at finite temperatures remains a difficult…

Quantum Gases · Physics 2013-03-29 T. P. Billam , P. Mason , S. A. Gardiner

The weakly interacting trapped Bose gases have been customarily described using the mean-field approximation in the form of the Gross-Pitaevskii equation. The mean-field approximation, however, has certain limitations, in particular it can…

Atomic Physics · Physics 2009-11-11 H. H. Sorensen , D. V. Fedorov , A. S. Jensen

Following the idea of the density functional approach, we develop a generalized Bogoliubov theory of an interacting Bose gas confined in a one-dimensional harmonic trap, by using a local chemical potential - calculated with the Lieb-Liniger…

Quantum Gases · Physics 2024-08-26 Xiao-Long Chen , Yun Li , Hui Hu

The idea is advanced that strong perturbations of an initially equilibrium Bose-condensed gas lead to the sequence of nonequilibrium states whose order is inverse to the sequence of states arising in the process of the Bose-gas relaxation…

Quantum Gases · Physics 2015-02-24 V. I. Yukalov , E. P. Yukalova

We study the detailed out of equilibrium time evolution of a homogeneous Bose-Einstein condensate.We consider a nonrelativistic quantum theory for a self-interacting complex scalar field, immersed in a thermal bath, as an effective…

Soft Condensed Matter · Physics 2009-10-31 Daniel G. Barci , E. S. Fraga , Rudnei O. Ramos

We experimentally and numerically investigate thermalization processes of a trapped $^{87}$Rb Bose gas, initially prepared in a non-equilibrium state through partial Bragg diffraction of a Bose-Einstein condensate (BEC). The system evolves…

Quantum Gases · Physics 2018-07-18 D. J. Brown , A. V. H. McPhail , D. H. White , D. Baillie , S. K. Ruddell , M. D. Hoogerland

We present a method for approximating the solution of the three-dimensional, time-dependent Gross-Pitaevskii equation (GPE) for Bose-Einstein condensate systems where the confinement in one dimension is much tighter than in the other two.…

Quantum Gases · Physics 2015-06-11 Mark Edwards , Michael Krygier , Hadayat Seddiqi , Brandon Benton , Charles W. Clark

We derive the equations for the non-linear effective dynamics of a so called pseudo-spinor Bose-Einstein condensate, which emerges from the linear many-body Schr\"odinger equation at the leading order in the number of particles. The…

Mathematical Physics · Physics 2017-10-19 Alessandro Michelangeli , Alessandro Olgiati

We systematically study the effects of higher-order quantum and thermal fluctuations on the stabilization of self-bound droplets in Bose mixtures employing the time-dependent Hartree-Fock-Bogoliubov theory. We calculate the ground-state…

Quantum Gases · Physics 2021-08-20 Nadia Guebli , Abdelaali Boudjemaa

The equilibration of a finite Bose system is modelled using a gradient expansion of the collision integral that leads to a nonlinear transport equation. For constant transport coefficients, it is solved in closed form through a nonlinear…

High Energy Physics - Phenomenology · Physics 2018-02-12 Georg Wolschin

The mean-field dynamics of a Bose-Einstein condensate is studied in presence of a microscopic trapping potential from which the condensate can escape via tunneling through finite barriers. We show that the method of complex scaling can be…

Soft Condensed Matter · Physics 2013-05-29 Peter Schlagheck , Tobias Paul

This study proposed a new numerical scheme for vortex lattice formation in a rotating Bose-Einstein condensate (BEC) using smoothed particle hydrodynamics (SPH) with an explicit real-time integration scheme. Specifically, the…

Quantum Gases · Physics 2023-04-19 Satori Tsuzuki

We study the numerical solution of the time-dependent Gross-Pitaevskii equation (GPE) describing a Bose-Einstein condensate (BEC) at zero or very low temperature. In preparation for the numerics we scale the 3d Gross-Pitaevskii equation and…

Condensed Matter · Physics 2009-11-10 Weizhu Bao , Dieter Jaksch , Peter A. Markowich

Phase-space methods allow one to go beyond the mean-field approximation to simulate the quantum dynamics of interacting fields. Here, we obtain a technique for initializing either Wigner or positive-P phase-space simulations of…

Quantum Physics · Physics 2020-01-08 King Ng , Rodney Polkinghorne , Bogdan Opanchuk , Peter D. Drummond

We provide a detailed description of the nonequilibrium time evolution of an interacting homogeneous Bose-Einstein condensate. We use a nonperturbative in-medium quantum field theory approach as a microscopic model for the Bose gas. The…

Soft Condensed Matter · Physics 2007-05-23 D. G. Barci , E. S. Fraga , Rudnei O. Ramos

In experiments, Bose-Einstein condensates are prepared by cooling a dilute Bose gas in a trap. After the phase transition has been reached, the trap is switched off and the evolution of the condensate observed. The evolution is…

Mathematical Physics · Physics 2014-04-18 Niels Benedikter