Interference of spin-orbit coupled Bose-Einstein condensates

TL;DR

This paper theoretically investigates how spin-orbit and Zeeman couplings affect interference patterns in noninteracting Bose-Einstein condensates with synthetic spin-orbit coupling, revealing robustness of quantum backflow.

Contribution

It provides a theoretical analysis of interference in spin-orbit coupled Bose-Einstein condensates under synthetic magnetic fields, highlighting the influence of spin interactions.

Findings

Interference patterns are strongly affected by spin-orbit and Zeeman couplings.

The angle between spins determines the interference pattern.

Quantum backflow remains robust despite spin-orbit and magnetic effects.

Abstract

Interference of atomic Bose-Einstein condensates, observed in free expansion experiments, is a basic characteristic of their quantum nature. The ability to produce synthetic spin-orbit coupling in Bose-Einstein condensates has recently opened a new research field. Here we theoretically describe interference of two noninteracting spin-orbit coupled Bose-Einstein condensates in an external synthetic magnetic field. We demonstrate that the spin-orbit and the Zeeman couplings strongly influence the interference pattern determined by the angle between the spins of the condensates, as can be seen in time-of-flight experiments. We show that a quantum backflow, being a subtle feature of the interference, is, nevertheless, robust against the spin-orbit coupling and applied synthetic magnetic field.