Time-resolved recombination dynamics of photoionized hydrogenlike impurities

The dynamics of recombination of photoionized shallow donors and free electrons is investigated on a nanosecond time scale by monitoring the photoconductive decay of high-purity n-type InP (μ≳${10}^5$ ${\mathrm{cm}}^2$ ${\mathrm{V}}^{\mathrm{-}1}$ ${\mathit{s}}^{\mathrm{-}1}$) after pulsed far-infrared excitation. The effects of several parameters (temperature, electric fields, doping concentration, and excitation intensity) on the recombination process have been investigated, and models are proposed to explain the observed phenomena, taking into account excited bound impurity states, impact ionization, and Auger processes.