||IMPROVEMENT OF CONTACT GRATING DEVICE FOR EFFICIENT TERAHERTZ WAVE GENERATION USING BI-ANGULAR FILTER
永島, 圭介 ,
坪内, 雅明 ,
越智, 義浩圓山, 桃子
journal of applied physics
We have proposed an improved contact grating device for generating terahertz waves efficiently and have succeeded in developing the device with a very high diffraction efficiency and a wide spectral width. This device has a bi-angular filter and a Fabry-Perot-type structure, which are composed of dielectric multilayers. The bi-angular filter is designed to reflect the 0th-order wave and transmit the -1st-order diffraction wave. Numerical calculations indicate that the new device has a maximum diffraction efficiency over 99% and a spectral width of approximately 20 nm. We measured a high efficiency of 90% over a broad spectral range using a fabricated device.