A Two-Channel Two-Frequency Low-Temperature Photodetector at Wavelengths of 119 and 220 μm of an H{sub}2O Laser

摘要

The design and characteristics of a compact device consisting of four cooled photodetectors of radiations at two frequencies (2.53 and 1.36 THz) are presented. The photodetectors are based on two pairs of Ge:Sb and n-type InSb single crystals and equipped with preamplifiers. The photodetector is intended for operating jointly with an H{sub}2O laser, which operates in a mode of generation of orthogonally polarized waves, and can be used in interferometers with insufficiently stable lengths of optical paths, e.g., during investigation of plasma in high-power pulsed facilities. The photodetector is manufactured in the form of an insert into a commercial portable helium Dewar flask with a 12-mm-diameter neck.