高重复频率相干衍射辐射超宽谱太赫兹源

High-repetition-rate ultra-broadband coherent diffraction radiation THz source

研究了一种新型相干衍射辐射(CDR)太赫兹源,该太赫兹源基于中国工程物理研究院自由电子激光相干强太赫兹源(FEL-THz)的加速器电子束束流,具有MHz量级重复频率。理论分析、数值计算和PIC模拟证明了此太赫兹源时间长度可达到ps量级,中心频率在100～400GHz可调,截止频率位于1～2THz,脉冲峰值功率可达10kW量级,平均功率可达到W量级,并且功率随束流流强成平方正比关系。

We proposed a coherent diffraction radiation （CDR） THz source with megahertz repetition rate, which is based on ultra-short electron beams of the free electron laser THz （FEL-THz） facility at CAEP. With theoretical analysis, numerical calculation and particle-in-cell （PIC） simulation, the pulse duration of this THz source is proved to be several picoseconds. The center frequency is tunable from 100 GHz to 400 GHz and the cut-off frequency is from 1 THz to 2 THz. The peak power is in 10 kW region and the average power can be a few watts. Furthermore, the THz power is proportional to the square of the electron beam current.