【作者】 张开春；

【导师】 刘盛纲；

【作者基本信息】 电子科技大学 ， 物理电子学， 2009， 博士

【摘要】 太赫兹波是介于远红外与毫米波之间的一种电磁辐射，有非常重要的学术和应用价值。本论文研究了一种太赫兹波扩展互作用振荡器(EIO)辐射源，进行了详细地理论研究和模拟研究以及实验研究，取得了令人满意的结果。本论文的主要工作和创新之处：一、提出一种适合于太赫兹波段的新型慢波结构——矩形重入耦合腔，作为太赫兹EIO的慢波谐振系统。二、在理论上详细研究了该慢波系统的特性。分别采用导体微扰原理和脊波导的等效电路参数，研究了矩形重入谐振腔的频率和电路参数。接着采用等效电路模型研究矩形重入耦合腔慢波系统的色散特性。同时选择0．12THz和0．225THz两个频段，进行了相应的计算。三、太赫兹波EIO的注-波互作用理论研究。在小信号的情况下，详细推导了电子注在各个间隙和漂移区中的运动方程、效率、电子归一化电导和起振电流等。利用大信号的电子圆盘模型，推导了各个电子圆盘在各个间隙和漂移区中的工作方程和在交界处的衔接方程。同时，采用MATLAB编制相应程序，在太赫兹频段中详细计算和讨论了以上这些参数，并确定了最佳工作距离。四、通过理论研究确定的结构尺寸，分别采用CST和MAGIC电磁模拟软件对慢波系统的场分布、模式、色散特性进行了模拟研究，计算了耦合阻抗和特征阻抗。对特定结构的色散特性，理论结果和模拟结果取得了很好的一致，表明理论研究所采取的模型和参数是准确的。然后，采用MAGIC粒子模拟软件对特定系统下的EIO进行了粒子模拟，对于圆形电子通道0．12THz、0．225THz和矩形电子通道0．215THz EIO，输出峰值功率分别为512W、44W和200W，研究表明EIO具有很宽的工作电压。五、结合国内的加工技术，尝试加工了0．11THz和0．22THz的慢波谐振系统。采取验证性实验方案，从8mm波段入手研制EIO整管，选择折叠波导作为慢波系统，以熟悉工艺和积累经验为目的，为今后的太赫兹EIO的研制奠定基础。设计了整管结构，采用圆柱状平板电子枪、线圈型脉冲磁场，进行了相应的整管实验研究，测试了阴极和电子枪性能测试、输出功率和频率，取得了初步的结果。这些实验研究获得了EIO工作的直观经验，为下一步进行太赫兹EIO的实验研究奠定了基础。更多还原

【Abstract】 Terahertz (THz) wave, electromagnetic radiation between far infrared and millimeter wave, has very important academic and application value. One kind of THz radiation source, extended interaction oscillator (EIO), is presented in this dissertation. The theoretical, simulation and experimental studies have been carried out in detail.The main work includes as the following:1. A novel slow wave structure (SWS) of rectangular reentrance coupled-cavity suitable for THz wave has been proposed as the SWS of THz EIO.2. The cold cavity characteristic of the SWS has been theoretically studied in detail. The frequency and the circuit parameters of a rectangular reentrance resonant cavity have been studied by the unperturbed theory and the principle of the equivalent circuit of a ridged waveguide, respectively. The circuit model and the dispersion characteristic of the SWS have been studied by adopting the equivalent circuit method.3. The beam-wave interaction in THz wave EIO has been studied. With the electrons motion equation, the beam-wave interaction efficiency and the normalized electron conductance as well as the staring current have been calculated in detail. From the concept of large signal based on electron disk model, each electron disk operating equations in each gap and drift zone and the matching equation at the boundary between the gap and the drift zone have been obtained. These parameters in THz wave region have been calculated and discussed in detail by programming. The optimal period number has been calculated.4. With CST and MAGIC software, the filed distribution, and the dispersion characteristic of the operating mode of the SWSs obtained by theoretical study have been simulated. The coupled impedance and characteristic impedance of the SWSs have been computed. The dispersion characteristic of the SWSs obtained by theoretical study agrees well with that by the simulation study. The beam-wave interaction of THz EIOs has been carried out by PIC (particle in cell) code. Simulation results have shown that the EIO output peek power are 512W, 44W and 200W at 0.12THz and 0.225THz with round beam tunnel and at 0.215THz with rectangular beam tunne, respectively. The study shows that THz EIOs can operate in very wide voltage.5. Combined with the domestic machining technique, high frequency circuits of 0.11THz EIO and 0.22THz EIO have been fabricated. The experiment of the EIO at 8mm band with U-shaped folded waveguide SWS has being carried out. The 8mm EIO tube has been designed including the SWS, the transferring waveguide, the electronic gun and the magnet. The preliminary experiments have been carried out, including the performance of the cathod and the electronic gun and the measurement of the output power and the operating frequency.更多还原