Mueller matrix ellipsometer based on discrete-angle rotating Fresnel rhomb compensators

A spectroscopic Mueller matrix ellipsometer based on two rotating Fresnel rhomb compensators with a nearly achromatic response and optimal retardance is described. In this instrument, the compensators rotate in a discrete manner instead of continuously rotating, and this allows for awell-conditioned measurement even for low intensity samples. Moreover, in this configuration, the exposure time of the CCD detector can be varied within orders of magnitude without interfering with the dynamics of the compensator rotation. An optimization algorithm determines the optimal set of discrete angles that allows the determination of the Mueller matrix in the presence of noise. The calibration of the instrument is discussed, and examples of experimentally determined Mueller matrices are provided. (C) 2021 Optical Society of America

Automated summary

This study introduces a spectroscopic Mueller matrix ellipsometer based on two rotating Fresnel rhomb compensators with nearly achromatic response and optimal retardance. The instrument allows for well-conditioned measurement even for low intensity samples due to the compensators rotating in a discrete manner instead of continuously rotating. An optimization algorithm determines the optimal set of discrete angles to determine the Mueller matrix in the presence of noise, and experimental Mueller matrices are provided as examples.