Tracking the polarisation state of light via Hong-Ou-Mandel interferometry

TL;DR

This paper introduces a statistically robust method using Hong-Ou-Mandel interferometry combined with maximum likelihood estimation to precisely measure and track the polarization state of light, achieving high accuracy and optimal information extraction.

Contribution

The paper presents a novel framework that combines quantum interferometry with statistical estimation techniques to improve polarization measurement precision.

Findings

Achieved 0.6 arcminute precision in polarization measurement.

Ensured the Cramér-Rao bound is saturated for optimal estimation.

Demonstrated the method's effectiveness in tracking polarization changes.

Abstract

We provide a statistically robust and accurate framework to measure and track the polarisation state of light employing Hong-Ou-Mandel interference. This is achieved by combining the concepts of maximum likelihood estimation and Fisher information applied to photon detection events. Such an approach ensures that the Cram\'er-Rao bound is saturated and changes to the polarisation state are established in an optimal manner. Using this method, we show that changes in the linear polarisation state can be measured with 0.6 arcminute precision (0.01 degrees).