Parametrized protocol achieving the Heisenberg limit in the optical domain via dispersive atom-light interactions

TL;DR

This paper proposes a parametrized atom-light interaction protocol in cavity-QED systems that can achieve Heisenberg-limited sensitivity in optical measurements, potentially enabling highly precise quantum metrology.

Contribution

It introduces a time-reversal protocol with holonomic unitary parametrization to attain the Heisenberg limit using nonclassical states in cavity-QED.

Findings

The protocol can reach the Heisenberg limit in sensitivity.

Appropriate initial states are crucial for ultimate sensitivity.

The scheme is experimentally feasible for quantum-enhanced measurements.

Abstract

The strong and collective atom-light interactions in cavity-QED systems perform manifold benefits in quantum-enhanced measurements. Here, we study the time-reversal protocol that has been proposed to sense small displacements of the light field, and report the sensitivity of the scheme that could be speeded up to attain the Heisenberg limit (HL).We show the holonomic unitary parametrization process of the scheme and one only need to choose appropriate initial states to pursue the ultimate sensitivity. The scheme may pave an experimentally feasible way to achieve Heisenberg-limited metrology with nonclassical states.