北大核科学论坛第185期
发布时间：2014-12-05
报告人：黄衍介(Yen-Chieh Huang)，台湾新竹清华大学电资学院光电研究所教授，新竹清华大学物理系合聘教授。台湾国立中山大学电机工程系本科毕业后就读于斯坦福大学电机工程系，先后获硕士、博士学位。研究领域包括准相位匹配非线性光学，相对论光电子学，波长可调激光系统，非线性纳微光电元件，兆赫兹激光等。
报告题目：Future Light Source driven by Dielectric Laser Accelerator
报告地点：技物楼射频超导实验室二楼会议室
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报告摘要：
A dielectric laser accelerator (DLA) accelerates charged particles by using a phase synchronized laser field in an optical dielectric structure. Owing to the high damage threshold of a dielectric, a DLA is expected to provide stable particle acceleration with a gradient approaching 1 GeV/m. To be compact, a future free-electron laser (FEL) driven by a DLA would prefer a dielectric laser undulator with a micro undulator period and a high undulator field. A short undulator period means a low energy beam from a DLA for a given radiation wavelength. When the radiation photon energy is not small compared with the electron kinetic energy, quantum recoil could knock the electron out of the FEL gain bandwidth and stop the FEL buildup. On the other hand, a DLA, with its size scaled by the laser wavelength, is capable of generating nano-meter electron bunches. Since the electron bunch length is already on the order of the x-ray wavelength, a DLA beam is well suited for generating intense coherent x-ray radiation or building up x-ray FEL from a short undulator. ?In my presentation, I will first introduce DLA and show a range of design parameters to avoid the disadvantageous quantum FEL regime, while take advantage of the coherent short-bunch radiation of a DLA beam for an ultra-compact x-ray FEL.
