Shot noise limited interferometry for measuring classical force

TL;DR

This paper introduces a shot noise limited interferometry method utilizing electromagnetically induced transparency to measure classical forces with back-action evasion, thermal noise suppression, and shot noise as the fundamental limit.

Contribution

The paper presents a novel interferometry technique that achieves back-action evasion and thermal noise suppression, enhancing force measurement sensitivity.

Findings

Back-action noise is eliminated in the proposed method.

Thermal noise can be negligible under certain conditions.

Sensitivity is limited only by shot noise.

Abstract

We propose an interferometry technique, by using electromagnetically induced transparency phenomena, for measuring classical force. The classical force is estimated by measuring the phase at the output of the interferometer. The proposed measurement mechanism satisfies quantum non-demolition measurement conditions leading to back-action evasion. We further derive the sufficient condition under which the thermal noise in the interferometer is negligible. With no back-action noise and no thermal noise, the sensitivity of this technique is limited by shot noise only.