Multi-Stability in Cavity QED with Spin-Orbit Coupled Bose-Einstein Condensate

TL;DR

This paper explores multi-stability phenomena in a cavity QED system with spin-orbit coupled Bose-Einstein condensates, revealing tunable multi-stable photon states and complex atomic population behaviors influenced by system parameters.

Contribution

It demonstrates the emergence and control of multi-stability and bi-unstable atomic populations in cavity QED with spin-orbit coupled BECs, a novel insight compared to previous studies.

Findings

Multi-stable cavity photon states can be tuned via system parameters.

Atomic populations exhibit bi-unstable and transitional interface behaviors.

Secondary interfaces emerge with increased mechanical dissipation.

Abstract

We investigate the occurrence of steady-state multi-stability in a cavity system containing spin-orbit coupled Bose-Einstein condensate and driven by a strong pump laser. The applied magnetic field splits the Bose-Einstein condensate into pseudo-spin states, which then became momentum sensitive with two counter propagating Raman lasers directly interacting with ultra-cold atoms. After governing the steady-state dynamics for all associated subsystems, we show the emergence of multi-stable behavior of cavity photon number, which is unlike with previous investigation on cavity-atom systems. However, this multi-stability can be tuned with associated system parameters. Further, we illustrate the occurrence of mixed-stability behavior for atomic population of the pseudo spin-$\uparrow$ amd spin-$\downarrow$ states, which are appearing in so-called bi-unstable form. The collective behavior of these atomic number states interestingly possesses a transitional interface among the population of both spin states, which can be enhance and controlled by spin-orbit coupling and Zeeman field effects. Furthermore, we illustrate the emergence of secondary interface mediated by increasing the mechanical dissipation rate of the pseudo-spin states. These interfaces could be cause by the non-trivial behavior of synthetic spin state mediated by cavity. Our findings are not only crucial for the subject of optical switching, but also could provide foundation for future studies on mechanical aspect of synthetic atomic states with cavity quantum electrodynamics.