基于大功率激光二极管的光导开关导通特性

研究了应用于介质壁加速器的小间隙光导开关在大功率激光二极管驱动下的导通特性。激光二极管产生的激光脉冲中心波长为905nm,脉冲宽度(FWHM)约20ns,前沿约3.1ns,抖动小于200ps,峰值功率约90W。所用光导开关为异面电极结构的砷化镓(GaAs)光导开关,电极间隙5mm,偏置电压为15~22kV脉冲高压,工作在非线性(高增益)模式。测得光导开关最小导通电阻4.1Ω,抖动小于1ns,偏置电压在18kV时平均使用寿命约200次。

Conduction characteristics of photoconductive semiconductor switches based on high power laser diodes

The characteristics of photoconductive semiconductor switches (PCSSs), based on laser diodes, are introduced in this paper, including the scheme and some finals in the experiments. This kind of switch may be used in the dielectric wall accelerator (DWA). The pulsed laser triggering the PCSS has the wavelength, full width at half maximum (FWHM), rise-time, and peak power of 905 nm, 20 ns, 3.1 ns and 90 W, respectively. The switch we used in the experiment is an opposed-contact GaAs photoconductive semiconductor switch. The electrode gap is 5 mm, and when the bias pulsed voltage is between 15 kV and 22 kV, the switch works in the nonlinear mode. The measured least closing resistance is 4.1 , root mean square (RMS) jitter is less than 1 ns, and the average life-time of PCSSs is approximately 200 shots under 18 kV bias pulsed voltage.