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arXiv · 1707.01578

Polarisation of THz synchrotron radiation: from its measurement to control

Meguya Ryu·Denver Linklater·William Hart·Armandas Balcytis·Edvinas Skliutas·Mangirdas Malinauskas·Dominique Appadoo·Yaw-Ren Eugene Tan·Junko Morikawa·Saulius Juodkazis
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Abstract

Polarisation analysis of synchrotron THz radiation was carried out with a standard stretched polyethylene polariser and revealed that the linearly polarised (horizontal) component contributes up to 22 +/- 5% to the circular polarised synchrotron emission extracted by a gold-coated mirror with a horizontal slit inserted near a bending magnet edge. Comparison with theoretical predictions shows a qualitative match with dominance of the edge radiation. Grid polarisers 3D-printed out of commercial acrilic resin were tested for the polariser function and showed spectral regions where the dichroic ratio DR > 1 and < 1 implying importance of molecular and/or stress induced anisotropy. Metal-coated 3D-printed THz optical elements can find a range of applications in intensity and polarisation control of THz beams.

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Meguya Ryu, Denver Linklater, William Hart, Armandas Balcytis, Edvinas Skliutas, Mangirdas Malinauskas, Dominique Appadoo, Yaw-Ren Eugene Tan, Junko Morikawa, Saulius Juodkazis. 2017-07-01. Polarisation of THz synchrotron radiation: from its measurement to control. https://arxiv.org/abs/1707.01578

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