Collision of two self-trapped atomic matter wave packets in an optical ring cavity

TL;DR

This paper investigates the collision dynamics of self-trapped atomic matter wave packets in an optical ring cavity, revealing velocity-dependent behaviors and phase sensitivity with potential applications in precision interferometry.

Contribution

It provides the first detailed analysis of collision phenomena of matter wave packets in an optical cavity, highlighting velocity effects and phase sensitivity not observed in cavity-free systems.

Findings

Low velocity collisions cause oscillations around equilibrium.

Medium velocities lead to scattering and fragmentation.

High velocities result in classical-like collisions with shape preservation.

Abstract

The interaction between atomic Bose-Einstein condensate (BEC) and light field in an optical ring cavity gives rise to many interesting phenomena such as supersolid and movable self-trapped matter wave packets. Here we examined the collision of two self-trapped atomic matter wave packets in an optical ring cavity, and abundant colliding phenomena have been found in the system. Depending on the magnitude of colliding velocity, the collision dynamics exhibit very different features compared with the cavity-free case. When the initial colliding velocities of the two wave packets are small, they correlatedly oscillate around their initial equilibrium positions with a small amplitude. Increasing the collision velocity leads to severe scattering of the BEC atoms; after the collision, the two self-trapped wave packets usually break into small pieces. Interestingly, we found that such a medium velocity collision is of great phase sensitivity, which may make the system useful in precision matter wave interferometry. When the colliding velocity is further increased, in the bad cavity limit, the two wave packets collide phenomenally similar to two classical particles -- they firstly approach each other, then separate with their shape virtually maintained. However, beyond the bad cavity limit, they experience severe spatial spreading.