太赫兹回旋管中若干物理问题的研究

项目名称： 太赫兹回旋管中若干物理问题的研究

项目编号： No.61471007

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 无线电电子学、电信技术

项目作者： 刘濮鲲

作者单位： 北京大学

项目金额： 96万元

中文摘要： 太赫兹科学技术在无线通信、医疗诊断、环境监测、雷达、安全检查、射电天文和材料检测等方面具有重要的应用前景，而太赫兹辐射源则是制约太赫兹科学技术发展的主要瓶颈之一。回旋管是基于电子回旋谐振受激辐射（ECRM）机理的一种相对论快波器件，在毫米波和太赫兹频段具有功率大和效率高的突出优点。然而，在目前太赫兹回旋管的发展中，亟需解决三个主要问题，即对强磁场的依赖、模式竞争和严重的欧姆损耗问题。为此，本项目拟针对这三个问题，开展太赫兹回旋管中对应的物理问题的研究。重点开展高次谐波ECRM的研究，以成倍降低系统所需的磁场强度，同时获得较高的输出功率和互作用效率；开展太赫兹频段ECRM系统的模式竞争机理和控制技术的研究，以有效管控各种不稳定性；发展高阶腔体模式ECRM系统，提高系统品质因数，降低欧姆耗散对太赫兹回旋管的影响。希望通过该项研究，打破太赫兹回旋管发展的关键屏障，推动太赫兹科学技术的发展。

中文关键词： 太赫兹；回旋管；谐波；模式竞争；欧姆损耗

英文摘要： Terahertz (THz) science and technology is of great prospects in applications including wireless communication, medical diagnosis, environmental monitoring, radar, safety inspection, radio astronomy and material testing. However, one of the major factors hindering the development of THz science and technology is the lack of available THz radiation sources. Gyrotron is a kind of relativistic fast-wave device, which is based on the mechanism of the electron cyclotron resonance maser (ECRM). Gyrotrons are with the outstanding advantages of high power and high efficiency in millimeter-wave and THz ranges. The problem is that, right at this stage of THz gyrotron development, there are three urgent challenges to be solved, namely the dependency on high magnetic field strength, mode competitions, and serous ohmic dissipation. For the purpose of overcoming the aforementioned challenges, systematic investigation on the fundamental physics of the THz gyrotron will be carried. The first attenuation will be paid to the high harmonic ECRM scheme to reduce the magnetic field strength by several times and simultaneously maintain relatively high output power and efficient interaction. Studying the mode competition mechanism and stabilizing technology, it is an effective way to bring various kinds of instabilities under control. Developing high-volume-mode ECRM system, it will enhance the Q-factor and suppress deteriorate influence from the ohmic dissipation to THz gyrotron. Intense efforts of this program will be devoted to breaking the crucial barriers limiting THz gyrotron development, and promoting the advancement of THz science and technology.

英文关键词： Terahertz;Gyrotron;Harmonic;Mode Competition;Ohmic Losses