Experimental research on GaAs photoconductive semiconductor switches triggered by laser diode

This paper introduces an experiment of 3 mm-gap GaAs photoconductive semiconductor switch (PCSS) triggered by laser diode，which produces nonlinear output on 600 load. The peak power of laser diode is 70 W，and its output rise-time and duration (FWHM) are 20 and 40 ns， respectively. Along with the bias electric field enhancement， the output voltage increases linearly； when the bias electric field exceeds the threshold， about 2.53 kV/mm， the output voltage increases rapidly after a small peak and delay， and the avalanche occurs. Experiment results indicate that the production of nonlinear output has relation to carrier accumulation and impact ionization in GaAs chip； the enhancement of bias electric field increases the number of collective carriers， the degree of impact ionization， and thus accelerate the switchs turn into avalanche mode.