Coherent quantum noise cancellation for torque sensing using auxiliary coupled Laguerre-Gaussian optorotational cavity

This work introduces a quantum-enhanced torque sensing methodology utilizing coherent quantum noise cancellation (CQNC) within a hybrid optomechanical architecture termed the auxiliary coupled Laguerre-Gaussian (LG) optorotational cavity. The setup comprises a primary rotational cavity supporting an LG optical mode interacting with a rotating mirror, alongside an auxiliary op- tical resonator embedding an effective two-level atomic ensemble that emulates a negative mass oscillator. Photon-hopping mediated inter-cavity coupling facilitates phase-coherent energy exchange, enabling engineered interference pathways that mitigate quantum back-action noise-the principal quantum limit in precision torque transduction. Through analytical derivation and spectral response analysis, we demonstrate that this configuration facilitates torque sensitivity surpassing the standard quantum limit (SQL) across a wide frequency band. The integration of heterodyne CQNC offers a tunable detection bandwidth, positioning the system as a strong candidate for high-precision metrology and quantum-limited force sensing applications. These results pave the way for developing advanced quantum torque sensors, thereby furthering both theoretical research and practical measurement methodologies.