Optical interferometry in the presence of large phase diffusion

TL;DR

This paper introduces a nearly optimal interferometric method using homodyne detection and coherent light to detect phase shifts despite large phase diffusion, achieving high sensitivity with few measurements without nonclassical light.

Contribution

The paper presents a new interferometric scheme that reaches the ultimate sensitivity bound under large phase diffusion using classical resources and minimal measurements.

Findings

Achieves near-optimal sensitivity with hundreds of measurements.

Does not require nonclassical light sources.

Effective in high phase diffusion environments.

Abstract

Phase diffusion represents a crucial obstacle towards the implementation of high precision interferometric measurements and phase shift based communication channels. Here we present a nearly optimal interferometric scheme based on homodyne detection and coherent signals for the detection of a phase shift in the presence of large phase diffusion. In our scheme the ultimate bound to interferometric sensitivity is achieved already for a small number of measurements, of the order of hundreds, without using nonclassical light.