Subnanosecond kinetics of recombination radiation of a high-voltage gallium arsenide diode in impact-ionization switching

Time-correlated single photon counting is used to examine the kinetics of recombination radiation of a high-voltage gallium arsenide diode in subnanosecond switching initiated by a rapid increase in reverse voltage. Switching proceeds along local current channels. It is demonstrated that the radiation intensity reaches its maximum within less than 80 ps, providing an upper estimate for the time of diode switching into the conducting state. The fall time of radiation intensity after switching is anomalously short (250–700 ps). A subnanosecond fall time of radiation intensity indicates that the concentration of non-equilibrium carriers in conducting channels is high and the threshold of stimulated emission is reached. The stimulated nature of radiation is verified by narrowing of the recombination spectrum.