Title :
Theoretical and Experimental Investigations on the Quasi-Optical Mode Converter for a Pulsed Terahertz Gyrotron
Author :
Diwei Liu ; Wei Wang ; Qianmeng Zhuang ; Yang Yan
Author_Institution :
Sch. of Phys. ElectronicsTerahertz Sci. & Technol. Res. Center, Univ. of Electron. Sci. & Technol. of China, Chengdu, China
Abstract :
Theoretical and experimental investigations on the quasi-optical (QO) mode converter for a 0.42 THz, TE26 mode pulsed gyrotron have been carried out. The vector diffraction theory and the multiple iterative algorithms are used to design and optimize the QO mode converter, and the theoretical value for the conversion efficiency is ~88%. The actual conversion efficiency is ~86% by measuring the input and output power of the QO mode converter indirectly with a calorimeter. The field distribution on the output window of the QO mode converter is measured with an infrared video camera, and a well-focused Gaussian-like beam has been observed on the output window. The experimental results agree well with the theoretical predictions.
Keywords :
Gaussian processes; calorimeters; convertors; gyrotrons; infrared detectors; infrared imaging; iterative methods; power measurement; submillimetre wave tubes; terahertz wave devices; vectors; video cameras; QO mode converter; TE26 mode; calorimeter; frequency 0.46 THz; infrared video camera; multiple iterative algorithm; power measurement; pulsed terahertz gyrotron; quasioptical mode converter; vector diffraction theory; well-focused Gaussian-like beam; Converters; Diffraction; Gyrotrons; Mirrors; Power generation; Power measurement; Vectors; Quasi-optical mode convertor; gyrotron; multiple iterative algorithms; terahertz; vector diffraction theory;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2014.2385872
