0.14THz双环超材料慢波结构表面波振荡器数值研究  

Numerical studies on a 0.14 THz coaxial surface wave oscillator with double-ring metamaterial slow wave structure

作　　者：郭伟杰[1] 陈再高[1,2] 蔡利兵[1,2] 王光强[2] 程国新[2] 

机构地区：[1]西安交通大学,电子与信息工程学院,西安710049 [2]西北核技术研究所,西安市710024

出　　处：《物理学报》2015年第7期171-177,共7页Acta Physica Sinica

摘　　要：本文研究了一种太赫兹波段双环超材料慢波结构,并具有同轴引出结构的相对论过模表面波振荡器.设计了超材料同轴过模慢波结构;通过色散特性,进行了模式选择和过模结构电子束电参数和几何参数的设计;根据超材料同轴慢波结构的特点,设计了具有同轴引出结构的末端同轴输出段.粒子模拟结果表明,在电子束电压为600 kV和电流为1.0 k A,引导磁场为2.0 T时,同轴超材料慢波结构过模表面波振荡器输出稳定单频的0.141 THz电磁波,峰值功率为316.8 MW.This paper presents a relativistic coaxial overmoded surface wave oscillator（SWO） working at the terahertz band in the double-ring metamaterial slow wave structure（SWS）. A relativistic electron beam passes through the SWS between the inner and outer rings. A coaxial overmoded SWS made up of metal metamaterial is designed to generate the high-power terahertz wave by increasing the beam-wave interaction efficiency and enlarging the transverse size of the terahertz device. It consists of double rings periodically arrayed along the z-direction, and a coaxial conductor with a radius of 2.4 mm. By its dispersive relation the proposed device is studied, from which we choose the 0.14 THz as the operating frequency of the device. Then the parameters of the geometric structure and the electron beam are optimized; the transitional section for extracting the terahertz signal is designed of the largest propagation coefficient.Particle simulation code UNIPIC is employed to verify the initial expectation and potential advantages. When the beam voltage and current are increasing, the operating frequency of the device remains almost constant, and this is the typical characteristic of the SWO. Particle simulation results show that the coaxial inner conductor has a stable operating mode of double-ring metamaterial SWS and can increase the beam-wave interaction efficiency of the SWO at the terahertz band. For a guiding magnetic field of 2.0 T, with the electron beam of 600 kV and a current of 1.0 k A, a 0.141 THz wave output power of 316.8 MW is obtained.

关 键 词：太赫兹 超材料慢波结构 表面波振荡器 同轴结构 

分 类 号：TN752[电子电信—电路与系统]