Theories of the Spectral Selective Photoelectric Effect

Abstract

Clean alkali surfaces emit less than one photoelectron for every 10,000 incident light quanta in the visible spectrum. A monomolecular layer of gas can greatly increase this yield. In this paper it is shown that mechanisms in which the metal electrons directly absorb the light can never give high efficiencies. A process is discussed in which alkali atoms outside the gas layer absorb light, their excitation energy then being transferred to the metal electrons. This process is shown capable of giving an efficiency comparable with the highest which has been observed.