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An integrable nonlinear model for the time-dependent equilibration of a bosonic system that has been devised earlier is solved exactly with boundary conditions that are appropriate for a truncated Bose-Einstein distribution, and include the…

Statistical Mechanics · Physics 2020-02-05 N. Rasch , G. Wolschin

We study the non-equilibrium evolution of binary Bose-Einstein condensates in the presence of weak random potential with a Gaussian correlation function using the time-dependent perturbation theory. We apply this theory to construct a…

Disordered Systems and Neural Networks · Physics 2021-12-28 Abdelaali Boudjemaa

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

Stemming from the Heisenberg equations of motion, we study the time-evolution stability of the order parameters for the cold atoms on optical lattices. The requirement of this stability of the order parameters endows the phase diagram with…

Soft Condensed Matter · Physics 2007-05-23 Yue Yu

It is shown, that Bose-Einstein condensation can occur not only in spatially extended equilibrium systems, but also in the systems far from thermal equilibrium, which show order-disorder phase transition. The investigation is performed by…

Soft Condensed Matter · Physics 2007-05-23 Kestutis Staliunas

We study experimentally the dissipative dynamics of ultracold bosonic gases in a dynamic disorder potential with tunable correlation time. First, we measure the heating rate of thermal clouds exposed to the dynamic potential and present a…

This study aims to construct a theoretical formulation of a nonequilibrium process for a system of Bose--Einstein condensate associated with a spontaneous symmetry breakdown. For this, Thermo Field Dynamics is used. We then describe the…

Quantum Gases · Physics 2021-05-26 T. Oyama , Y. Nakamura , Y. Yamanaka

The non-Markoffian transport equations for the systems of cold Bose atoms confined by a external potential both without and with a Bose-Einstein condensate are derived in the framework of nonequilibrium thermal filed theory (Thermo Field…

Quantum Gases · Physics 2010-07-13 Y. Nakamura , T. Sunaga , M. Mine , M. Okumura , Y. Yamanaka

We study the dynamics of Bose-Einstein condensates flowing in optical lattices on the basis of quantum field theory. For such a system, a Bose-Einstein condensate shows a unstable behavior which is called the dynamical instability. The…

Other Condensed Matter · Physics 2009-11-13 K. Kobayashi , M. Mine , M. Okumura , Y. Yamanaka

In a trapped Bose-Einstein condensate, subject to the action of an alternating external field, coherent topological modes can be resonantly excited. Depending on the amplitude of the external field and detuning parameter, there are two…

Quantum Physics · Physics 2007-09-25 E. R. F. Ramos , L. Sanz , V. I. Yukalov , V. S. Bagnato

We theoretically study how the superfluid and condensate deformation of a weakly interacting ultracold Bose gas evolve during the ramp-up of an external weak disorder potential. Both resulting deformations turn out to consist of two…

Quantum Gases · Physics 2026-01-21 Rodrigo P. A. Lima , Milan Radonjić , Axel Pelster

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

We consider a time-dependent extension of a perturbative mean-field approach to the dirty boson problem by considering how switching on and off a weak disorder potential affects the stationary state of an initially equilibrated…

Quantum Gases · Physics 2021-01-20 Milan Radonjić , Axel Pelster

We study the nonequilibrium dynamics of a many-body bosonic system on a lattice, subject to driving and dissipation. The time-evolution is described by a master equation, which we treat within a generalized Gutzwiller mean field…

Quantum Gases · Physics 2013-05-29 Andrea Tomadin , Sebastian Diehl , Peter Zoller

We investigate the strong out-of-equilibrium dynamics occurring when a harmonically trapped ultracold bosonic gas is evaporatively cooled across the Bose--Einstein condensation transition. By imaging the cloud after free expansion, we study…

Quantum Gases · Physics 2022-03-29 Wolswijk L. , Mordini C. , Farolfi A. , Trypogeorgos D. , Dalfovo F. , Zenesini A. , Ferrari G. , Lamporesi G

We calculate the time evolution of a far-from-equilibrium initial state of a non-relativistic ultracold Bose gas in one spatial dimension. The non-perturbative approximation scheme is based on a systematic expansion of the two-particle…

Other Condensed Matter · Physics 2008-11-26 T. Gasenzer , J. Berges , M. G. Schmidt , M. Seco

The dynamical phase transition of a system with two coexisting competing order parameters is studied using the time-dependent-Ginzburg-Landau framework. The dynamics are induced by parameters capturing the physics of driving the system with…

Strongly Correlated Electrons · Physics 2025-08-19 Yasamin Masoumi Sefidkhani , Alberto de la Torre , Gregory A. Fiete

Construction, in the framework of a Nonequilibrium Statistical Ensemble Formalism, of a Mesoscopic Hydro-Thermodynamics, that is, covering phenomena involving motion displaying variations short in space and fast in time -unrestricted values…

Fluid Dynamics · Physics 2012-10-30 C. A. B. Silva , J. G. Ramos , A. R. Vasconcellos , R. Luzzi

Time evolution of a perturbed thermal state is studied in a quantum-mechanical system with O(N) symmetry. In the limit of large N, time dependence of O(N)-singlet expectation values can be described by classical equations of motion in a…

Quantum Physics · Physics 2009-03-26 P. V. Buividovich

Non-stationary long-time dynamics was recently observed in a driven two-component Bose-Einstein condensate coupled to an optical cavity [N. Dogra, et al. arXiv:1901.05974] and analyzed in mean-field theory. We solve the underlying model in…

Quantum Physics · Physics 2020-01-01 Berislav Buca , Dieter Jaksch
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