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arXiv · 1408.1650

A broadband silicon quarter-wave retarder for far-infrared spectroscopic circular dichroism

Xiaoxiang Xi·R. J. Smith·T. N. Stanislavchuk·A. A. Sirenko·S. N. Gilbert·J. J. Tu·G. L. Carr
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Abstract

The high brightness, broad spectral coverage and pulsed characteristics of infrared synchrotron radiation enable time-resolved spectroscopy under throughput-limited optical systems, as can occur with the high-field magnet cryostat systems used to study electron dynamics and cyclotron resonance by far-infrared techniques. A natural extension for magnetospectroscopy is to sense circular dichroism, i.e. the difference in a material's optical response for left and right circularly polarized light. A key component for spectroscopic circular dichroism is an achromatic 1/4 wave retarder functioning over the spectral range of interest. We report here the development of an in-line retarder using total internal reflection in high-resistivity silicon. We demonstrate its performance by distinguishing electronic excitations of different handednesses for GaAs in a magnetic field. This 1/4 wave retarder is expected to be useful for far-infrared spectroscopy of circular dichroism in many materials.

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Xiaoxiang Xi, R. J. Smith, T. N. Stanislavchuk, A. A. Sirenko, S. N. Gilbert, J. J. Tu, G. L. Carr. 2014-08-07. A broadband silicon quarter-wave retarder for far-infrared spectroscopic circular dichroism. https://doi.org/10.1016/j.infrared.2014.09.004

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