Cascaded Optomechanical Sensing for Small Signals

TL;DR

This paper introduces a classical, Heisenberg-limited optomechanical sensing scheme using a chain of coupled cavities, enabling high-precision detection of weak forces without quantum entanglement.

Contribution

It presents a novel, fully classical approach to achieve quantum-like sensitivity scaling in force sensing using optomechanical cavity chains.

Findings

Achieves Heisenberg-limited sensitivity without entanglement.

Utilizes coherent averaging in a chain of optomechanical cavities.

Potential applications include gravitational and dark matter detection.

Abstract

We propose a sensing scheme for detecting weak forces that achieves Heisenberg-limited sensitivity without relying on entanglement or other non-classical resources. Our scheme utilizes coherent averaging across a chain of N optomechanical cavities, unidirectionally coupled via a laser beam. As the beam passes through the cavities, it accumulates phase shifts induced by a common external force acting on the mechanical elements. Remarkably, this fully classical approach achieves the sensitivity scaling typically associated with quantum-enhanced protocols, providing a robust and experimentally feasible route to precision sensing. Potential applications range from high-sensitivity gravitational field measurements at the Large Hadron Collider to probing dark matter interactions and detecting gravitational waves. This work opens a new pathway for leveraging coherent light-matter interactions for force sensing.