<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Li Luo</style></author><author><style face="normal" font="default" size="100%">Chao-Hai Du*</style></author><author><style face="normal" font="default" size="100%">Xiang-Bo Qi</style></author><author><style face="normal" font="default" size="100%">Zheng-Di Li</style></author><author><style face="normal" font="default" size="100%">Shi Pan</style></author><author><style face="normal" font="default" size="100%">Ming-Guang Huang</style></author><author><style face="normal" font="default" size="100%">Pu-Kun Liu*</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Controllable thermal-frequency tuning of a THz gyrotron</style></title><secondary-title><style face="normal" font="default" size="100%">IEEE Trans. Electron Devices</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2018</style></year></dates><urls><web-urls><url><style face="normal" font="default" size="100%">https://ieeexplore.ieee.org/document/8240959/</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">65</style></volume><pages><style face="normal" font="default" size="100%">695-703</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Gyrotron performance is sensitive to cavity structure parameters, and the cavity shape is temperature dependent due to thermal deformation induced by temperature rise from ohmic loss power on finite-conductivity cavity wall. Accordingly, this paper studies a frequency-tuning scheme for terahertz gyrotron by properly controlling the cavity thermal deformation. By combining gyrotron nonlinear theory and finite-element method software, controllable thermal-frequency-tuning capability of a continuous-wave 263-GHz gyrotron is systematically investigated, toward maintaining gyrotron operating under gyromonotron condition in frequency-tuning band, and achieving high efficiency in broadband frequency-tuning range. After studying cavity thermal distribution, structure deformation, and electron beam-wave interaction, an optimized cavity structure with transition sections on both ends is proposed. Simulation predicts that with the two-transition-section cavity, via additional thermal tuning, the continuous-frequency-tuning band is capable of reaching 1.75 GHz, which is 5 times of the initial bandwidth. Furthermore, using the thermal-frequency-tuning technology, impressive high efficiency above 17% is obtainable in the whole frequency-tuning range.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue></record></records></xml>