Decoherence in a quantum harmonic oscillator monitored by a Bose-Einstein condensate

TL;DR

This paper explores how a quantum harmonic oscillator's coherence is affected by measurement via a Bose-Einstein condensate, revealing different decoherence regimes depending on measurement variables and BEC states.

Contribution

It introduces a model of oscillator-BEC interaction showing variable decoherence behaviors, including coherent, slow, and rapid decoherence regimes.

Findings

Oscillator experiences decoherence depending on measurement variables.

Decoherence regimes include coherent, power-law, and Gaussian decay.

Measurement type and BEC state influence decoherence dynamics.

Abstract

We investigate the dynamics of a quantum oscillator, whose evolution is monitored by a Bose-Einstein condensate (BEC) trapped in a symmetric double well potential. It is demonstrated that the oscillator may experience various degrees of decoherence depending on the variable being measured and the state in which the BEC is prepared. These range from a `coherent' regime in which only the variances of the oscillator position and momentum are affected by measurement, to a slow (power law) or rapid (Gaussian) decoherence of the mean values themselves.