研制了一种脉冲展宽型X射线光电二极管,并利用飞秒激光进行了验证。在光电阴极加载随时间变化的斜坡脉冲,使阴极与栅网之间产生一个随时间变化的电场,变化的电场赋予光电子轴向的速度色散,使较早产生的电子的移动速度快于较晚出现的电子。光电子进入漂移区,在到达微通道板(MCP)前被展宽,放大后的信号由示波器读出。应用脉冲展宽技术后,探测器的响应时间可提高约11倍。

A pulse-dilation X-ray diodes (XRD) is developed and also tested using a femtosecond laser. A time-dependent ramp waveform is applied to a photocathode (PC) to introduce a time-dependent electric field between PC and mesh. This electric field leads to an axial speed dispersion of the photoelectron signal. The electrons generated earlier move faster than those later. The photoelectrons transiting a drift region are stretched before reaching a microchannel plate (MCP), and are then amplified and read out with a digital oscilloscope. The detector's time response is enhanced by 11 times with the usage of pulse-dilation technique.