Nonlinear dynamics of a cigar-shaped Bose-Einstein condensate coupled with a single cavity mode

TL;DR

This paper explores the complex nonlinear behavior of a Bose-Einstein condensate coupled with an optical cavity, revealing phenomena like bistability and adiabaticity breakdown due to system nonlinearity.

Contribution

The study introduces a discrete-mode approximation and maps steady states, uncovering nonlinear level folding and stability properties in the coupled system.

Findings

Nonlinear levels can fold, causing adiabaticity breakdown.

Optical bistability arises from the nonlinear dynamics.

Steady configurations are mapped using the discrete-mode approximation.

Abstract

We investigate the nonlinear dynamics of a combined system which is composed of a cigar-shaped Bose-Einstein condensate and an optical cavity. The two sides couple dispersively. This system is characterized by its nonlinearity: after integrating out the freedom of the cavity mode, the potential felt by the condensate depends on the condensate itself. We develop a discrete-mode approximation for the condensate. Based on this approximation, we map out the steady configurations of the system. It is found that due to the nonlinearity of the system, the nonlinear levels of the system can fold up in some parameter regimes. That will lead to the breakdown of adiabaticity. Analysis of the dynamical stability of the steady states indicates that the same level structure also results in optical bistability.