Spin measurements and control of cold atoms using spin-orbit fields

TL;DR

This paper demonstrates how spin-orbit interactions in cold-atom systems can simulate quantum measurements on spins, revealing diverse decoherence behaviors and resulting in observable density and interference patterns.

Contribution

It introduces a method to simulate quantum measurement processes in cold-atom systems using spin-orbit coupling, exploring different measurement regimes and their effects.

Findings

Access to ergodic and Zeno measurement regimes

Decoherence can be Gaussian or inverse fractional power law

Measurement back action causes density profiles and interference patterns

Abstract

We show that by switching on a spin-orbit interaction in a cold-atom system, experiencing a Zeeman-like coupling to an external field, e.g., in a Bose-Einstein condensate, one can simulate a quantum measurement on a precessing spin. Depending on the realization, the measurement can access both the ergodic and the Zeno regimes, while {the time dependence} of the spin's decoherence may vary from a Gaussian to an inverse fractional power law. Back action of the measurement forms time- and coordinate-dependent profiles of the atoms' density, resulting in its translation, spin-dependent fragmentation, and appearance of interference patterns.