Transient Internal Photoemission of Carriers in the Metal-Insulator System

Abstract

The transient photoemission of hot carriers from metals into insulators permits a detailed study of the dynamics of the metal-insulator interface. The technique can be viewed as the simulation of a transient thermionic experiment. The photoemission of electrons from copper into single-crystal CdS and holes from gold into amorphous selenium is reported. The results are consistent with a model of backscattering out of the insulator due to interaction with the lattice. Significant differences are found between photoemission into the single crystal and amorphous insulator which could arise from the different charge transport properties of these materials, as for example dictated by their structures.