Precision polarimetry with real-time mitigation of optical-window birefringence

TL;DR

This paper presents a real-time method to measure and compensate for optical-window birefringence, significantly reducing false polarization signals in precision polarimetry experiments.

Contribution

The authors introduce a reflection-based technique to measure and mitigate optical-window birefringence effects in real-time, improving measurement accuracy.

Findings

False signals reduced to about 1%

Effective for ellipticity less than 0.25 rad

Enhances precision in polarization measurements

Abstract

Optical-window birefringence is frequently a major obstacle in experiments measuring changes in the polarization state of light traversing a sample under investigation. It can contribute a signal indistinguishable from that due to the sample and complicate the analysis. Here, we explore a method to measure and compensate for the birefringence of an optical window using the reflection from the last optical surface before the sample. We demonstrate that this arrangement can cancel out false signals due to the optical-window birefringence-induced ellipticity drift to about 1%, for the values of total ellipticity less than 0.25 rad.