Cadmium zinc telluride as a mid-infrared variable retarder
Date
2018
Authors
FitzGerald, William
Taherion, Saeid
Kumar, F. Joseph
Giles, David
Hore, Dennis K.
Journal Title
Journal ISSN
Volume Title
Publisher
Journal of Applied Physics
Abstract
The electro-optic behavior of cadmium zinc telluride is examined in the mid-infrared region between 3 and 11 μm, for applied DC field strengths of up to 106 V/m. The measurements performed here include full characterization of the polarization state of the transmitted light by means of the Stokes vector. We demonstrate the suitability of this material for DC variable retarder applications such as those achieved by quarter- or half-wave retardation. A comparison of two different metallic coatings for electrodes, gold and indium, reveals important differences in performance that are attributed to the homogeneity of the field through the bulk of the crystal. We illustrate that, in the case of both metals, the same electro-optic coefficients are measured, but regions of higher and lower retardation result in significant depolarization in the case of gold. Such depolarization may adversely affect the contrast ratio in a light valve, or increase the voltage necessary for the operation of an arbitrary polarization state generator.
Description
Keywords
Semiconductors, Electro-optic coefficient, Work functions, Transition metals, Optical metrology, Chemical elements, Polarization, Geometrical optics, Optical coatings, Optical polarimetry
Citation
FitzGerald, W.; Taherion, S.; Kumar, F. J.; Giles, D.; & Hore, D. (2018). Cadmium zinc telluride as a mid-infrared variable retarder. Journal of Applied Physics, 123, 133103. DOI: 10.1063/1.5020320