Squeezing multilevel atoms in dark states via cavity superradiance

TL;DR

This paper proposes a method to generate and store long-lived, entangled spin-squeezed states in multilevel atoms within optical cavities, leveraging dark states and superradiance for quantum metrology applications.

Contribution

It introduces a novel approach to create and preserve spin-squeezed states in dark states using cavity superradiance and coherent driving, enabling scalable quantum state storage.

Findings

Squeezing can be generated in dark states immune to superradiance.

Squeezing can be transferred from bright to dark states via single-particle rotations.

Method is compatible with current optical cavity experiments.

Abstract

We describe a method to create and store scalable and long-lived entangled spin-squeezed states within a manifold of many-body cavity dark states using collective emission of light from multilevel atoms inside an optical cavity. We show that the system can be tuned to generate squeezing in a dark state where it will be immune to superradiance. We also show more generically that squeezing can be generated using a combination of superradiance and coherent driving in a bright state, and subsequently be transferred via single-particle rotations to a dark state where squeezing can be stored. Our findings, readily testable in current optical cavity experiments with alkaline-earth-like atoms, can open a path for dissipative generation and storage of metrologically useful states in optical transitions.