Weak measurements and the joint estimation of phase and phase diffusion

TL;DR

This paper explores the use of weak measurements for estimating phase and phase diffusion simultaneously in quantum systems, particularly in polarimetry, to improve multi-parameter quantum estimation.

Contribution

It introduces a framework for applying weak measurements to jointly estimate phase and phase diffusion, addressing limitations of traditional measurement techniques.

Findings

Weak measurements can optimize information extraction in multi-parameter quantum estimation.

The method is applicable to polarimetry scenarios involving phase diffusion.

Potential improvements in measurement precision for quantum systems with noise.

Abstract

Weak measurements offer the possibility of tuning the information acquired on a system, hence the imposed disturbance. This suggests that it could be a useful tool for multi-parameter estimation, when two parameters can not be measured simultaneously at the quantum limit. Here we discuss their use for phase estimation in the presence of phase diffusion in the context of polarimetry, a scenario which is conveniently cast in terms of a two-level quantum system in many relevant cases.