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arXiv · 1610.07071

Fabrication and Analysis of Three-Layer All-Silicon Interference Optical Filter with Sub-Wavelength Structure toward High Performance Terahertz Optics

Hironobu Makitsubo·Takehiko Wada·Hirokazu Kataza·Makoto Mita·Toyoaki Suzuki·Keita Yamamoto
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Abstract

We propose an all-silicon multi-layer interference filter composed solely of silicon with sub-wavelength structure (SWS) in order to realize high performance optical filters operating in the THz frequency region with robustness against cryogenic thermal cycling and mechanical damage. We demonstrate fabrication of a three-layer prototype using well-established common micro-electro-mechanical systems (MEMS) technologies as a first step toward developing practical filters. The measured transmittance of the three-layer filter agrees well with the theoretical transmittances calculated by a simple thin-film calculation with effective refractive indices as well as a rigorous coupled-wave analysis simulation. We experimentally show that SWS layers can work as homogeneous thin-film interference layers with effective refractive indices even if there are multiple SWS layers in a filter.

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Hironobu Makitsubo, Takehiko Wada, Hirokazu Kataza, Makoto Mita, Toyoaki Suzuki, Keita Yamamoto. 2016-10-22. Fabrication and Analysis of Three-Layer All-Silicon Interference Optical Filter with Sub-Wavelength Structure toward High Performance Terahertz Optics. https://doi.org/10.1007/s10762-016-0328-z

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