Photon bubbles in ultra-cold matter

TL;DR

This paper demonstrates the excitation of photon bubbles in ultra-cold atomic gases within a magneto-optical trap, revealing new instability regimes driven by light-matter interactions that could inform both laboratory and astrophysical phenomena.

Contribution

It introduces the concept of photon bubble instabilities in ultra-cold matter and analyzes their behavior using a coupled radiation transport and mean field model.

Findings

Identification of static and oscillating photon bubbles in cold atom gases.

Discovery of two regimes: oscillating and purely growing bubbles.

Potential implications for understanding turbulence in astrophysical contexts.

Abstract

We show that static and oscillating photon bubbles can be excited by diffused light in the laser cooled matter confined in a magneto-optical trap (MOT). The bubble instability is due to the coupling between the radiation field and the mean field oscillations of the ultra-cold gas, and it can provide a source for low frequency turbulence. We consider a diffusion dominated regime, which can be described by a radiation transport equation, coupled with the mean field equations for the cold atom gas. A perturbative analysis shows the occurrence of two different regimes with either oscillating or purely growing bubbles. This work could also be useful to understand similar processes in astrophysics.