Measurement back-action on the quantum spin-mixing dynamics of a spin-1 Bose-Einstein condensate

TL;DR

This paper investigates how measurement back-action influences the spin-mixing dynamics of a spin-1 Bose-Einstein condensate within an optical cavity, highlighting the dependence on measurement strength and quantum fluctuations.

Contribution

It introduces a stochastic master equation approach to analyze measurement back-action effects on spinor condensate dynamics in cavity QED systems.

Findings

Back-action effects depend on measurement strength and quantum fluctuations.

Identification of atom number thresholds where back-action hampers spin dynamics extraction.

Demonstration of measurement back-action's impact on quantum spinor condensate behavior.

Abstract

We consider a small F=1 spinor condensate inside an optical cavity driven by an optical probe field, and subject the output of the probe to a homodyne detection, with the goal of investigating the effect of measurement back-action on the spin dynamics of the condensate. Using the stochastic master equation approach, we show that the effect of back-action is sensitive to not only the measurement strength but also the quantum fluctuation of the spinor condensate. The same method is also used to estimate the atom numbers below which the effect of back-action becomes so prominent that extracting spin dynamics from this cavity-based detection scheme is no longer practical.