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arXiv · 1203.5019

Polarization modulation time-domain terahertz polarimetry

C. M. Morris·R. Valdés Aguilar·A. V. Stier·N. P. Armitage
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Abstract

We present high precision measurements of polarization rotations in the frequency range from 0.1 to 2.5 THz using a polarization modulation technique. A motorized stage rotates a polarizer at ~80 Hz, and the resulting modulation of the polarization is measured by a lock-in technique. We achieve an accuracy of 0.05{\deg} (900 {\mu}rad) and a precision of 0.02{\deg} (350 {\mu}rad) for small rotation angles. A detailed mathematical description of the technique is presented, showing its ability to fully characterize elliptical polarizations from 0.1 to 2.5 THz.

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C. M. Morris, R. Valdés Aguilar, A. V. Stier, N. P. Armitage. 2012-03-22. Polarization modulation time-domain terahertz polarimetry. https://doi.org/10.1364/oe.20.012303

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