Influence of optical pulse width on jitter and domain evolution of gallium arsenide photoconductive semiconductor switches

The delay time of a gallium arsenide photoconductive semiconductor switch (GaAs PCSS) fundamentally affects its synchronization stability. In this paper, a numerical computational model applicable to the simulation of GaAs PCSS current filaments with opposed-contact electrode structures in nonlinear mode is developed, and the impacts of optical pulse width and optical energy on switching delay are studied. The experimental results demonstrate that both optical pulse width and energy are correlated with switching jitter, and that higher optical energy and narrower pulse width can lead to lower jitter. Based on this result, the multiple avalanche domain theory is employed to analyze the influence of optical pulse width on domain evolution during the switching stage. The results reveal that narrower pulse widths accelerate the formation of avalanche domains, thereby shortening the switching time of the PCSS.