Two-Photon Photogeneration in Amorphous Selenium

Abstract

Two-photon photogeneration has been observed in amorphous selenium. The field dependence of this uniform bulk photogeneration process saturates at low fields and fits a Poole-Frenkel model down to 300 V/cm. The previously reported strong field dependence of the generation efficiency at low fields for strongly absorbed light is attributed to surface recombination.