Investigation of Circular Comb Slow-Wave Structure of THz Backward-Wave Oscillators
Wang Zi-cheng① Lu De-jian①② Wang Li① Li Hai-qiang① Zhang Shi-jie① Xu An-yu① Hao Bao-liang① Song Pei-de① Dai Zhi-hao①
①(Institute of Electronics, Chinese Academy of Science, Beijing 100190, China) ②(Graduate University of Chinese Academy of Science, Beijing 100039, China)
Abstract:3-D electromagnetic simulation software is used to calculate the dispersion and interaction impedance of circular comb Slow-Wave Structure (SWS) which works for Terahertz (THz) Backward-wave Oscillators (BWO). The results show that the inner radius of SWS is 0.175mm in the band of 430-570GHz, and the inner radius of SWS is 0.1mm in the band of 760-940GHz. The large radius of SWS is a great help for improving beam transmission. The interaction impedance of fundamental backward wave of the SWS is smaller than 1Ω is a good explain to the truth that the electronic efficiency of THz BWO is smaller than 0.01%.