中物院高功率THz FEL装置的理论分析和优化设计

摘要

在1～3 THz频段内设计了11个分点频率,对每一频率的对应的场强和电子束能量进行了选取和计算.模拟结果表明:采用目前参数基本能够达到设计要求；辐射频段在2.6 THz附近时装置输出功率和增益都比较高,可以先锁定这个频段附近进行实验的调试；在长波段即1 THz左右时,滑移效应显著,腔增益和输出功率较低,实验实现比较困难,因此在1 THz频段附近必须积极想办法来提高输出功率.%Design and simulations of the CAEP high power THz free electron laser(FEL) have been carried out using our 3D-Osifel code. The main work focuses on the optimization of different schemes through physical analysis. The wiggler peak field strength and electron beam energy have been selected with eleven frequencies ranging from 1 THz to 3 THz. The gain and power of resonator are calculated, which are corresponding to eleven frequencies. It can be seen that when the facility works at 2. 6 THz, the gain and output power are high. So the experiment may be conducted at this frequency first. When the device works at 1 THz, the slippage effect between the electron beam and radiation increases due to the increase of the radiation wavelength, which results in lack of overlapping between the electron and the optical pulses, then, the gain and output power lower. So experiment running at 1 THz could be challenged and further probe work should been put forward to solve the problem.