Entanglement-enhanced quantum sensing via optimal global control with neutral atoms in a cavity

TL;DR

This paper introduces a deterministic protocol for creating entangled states in atomic ensembles within a cavity, enhancing quantum sensing precision beyond classical limits despite noise and losses.

Contribution

It combines a geometric phase gate, analytic noisy channel solutions, and optimal control to generate entangled states for improved quantum sensing.

Findings

Achieves precision surpassing the standard quantum limit

Provides a deterministic entanglement protocol in cavity QED systems

Demonstrates robustness against cavity loss and decoherence

Abstract

We present a deterministic protocol for the preparation of entangled states in the symmetric Dicke subspace of $N$ spins coupled to a common cavity mode that prepares entangled states useful for quantum sensing, achieving a precision significantly better than the standard quantum limit in the presence of photon cavity loss, spontaneous emission and dephasing. The protocol combines a new geometric phase gate which can be utilized for exact unitary synthesis on the Dicke subspace, an analytic solution of the noisy quantum channel dynamics and optimal control methods. This work opens the way to entanglement-enhanced sensing with cold trapped atoms in cavities and is extendable to other spin systems coupled to a bosonic mode.