Photo-induced conduction in silver metaphosphate glass

We observed photo-induced conduction in silver- or gold-electroded silver metaphosphate glass by illumination from a mercury lamp. Photo-illumination caused photoelectron emission from the electrode surface. The silver or gold ions thus generated were neutralized by the electrons from the outside. Some of the electrons photo-generated were unable to escape the surface and caused charging, by which the conduction current through the glass was induced. Comparison was made with alumina ceramics in place of glass.