Relaxation of the Bose-condensate oscillations in the mesoscopic system at T=0

TL;DR

This paper investigates how nonlinear interactions cause nonmonotonic, dissipationless relaxation of transverse Bose-condensate oscillations at zero temperature, highlighting the role of parametric resonance and mode coupling.

Contribution

It introduces a model describing dissipationless relaxation of Bose-condensate oscillations via nonlinear mode coupling and parametric resonance at T=0.

Findings

Nonlinear mode coupling leads to nonmonotonic relaxation.

Parametric resonance couples transverse and longitudinal modes.

Energy return is suppressed, preventing dissipation.

Abstract

The general system is given of nonlinear equations describing dissipationless evolution of the oscillating Bose-condensate. The relaxation of transverse oscillations of the condensate in a trap of the cylindric symmetry is considered. The evolution occurs due to parametric resonance coupling the transverse mode with the longitudinal ones. The nonlinear rescattering in the subsystem of discrete longitudinal modes results in suppression of the return of energy, yielding dissipationless nonmonotonic relaxation of transverse oscillations in the condensate.