Mechanism for the dependence of the photoemission threshold of a photocathode on its irradiance

Secondary electron emission is shown to occur at the boundary of the working region of a photocathode when current flows through this region, causing a deviation from the known classical laws of photoemission. It is established that the sensitivity and photoemission threshold of the photocathode depend on the strength of the photocurrent flowing through it. Pis’ma Zh. Tekh. Fiz. 24, 1–6 (September 26, 1998)