Quantum noise reduction using a cavity with a Bose Einstein condensate

TL;DR

This paper explores how a Bose Einstein condensate coupled to an optical cavity can be used to control quantum noise, demonstrating phenomena like normal mode splitting and quantum squeezing of light.

Contribution

It introduces a novel optomechanical system where BEC density excitations influence quantum noise reduction and analyzes the effects of atomic interactions on mode splitting.

Findings

Normal mode splitting depends on two-body interaction strength.

Density excitations can squeeze quantum fluctuations of light.

System enables optomechanical control of quantum noise using BEC.

Abstract

We study an optomechanical system in which the collective density excitations (Bogoliubov modes) of a Bose Einstein condensate (BEC) is coupled to a cavity field. We show that the optical force changes the frequency and the damping constant of the collective density excitations of the BEC. We further analyze the occurrence of normal mode splitting (NMS) due to mixing of the fluctuations of the cavity field and the fluctuations of the condensate with finite atomic two-body interaction. The NMS is found to vanish for small values of the two-body interaction. We further show that the density excitations of the condensate can be used to squeeze the output quantum fluctuations of the light beam. This system may serve as an optomechanical control of quantum fluctuations using a Bose Einstein condensate.