Photoelectric Properties of Thin Unbacked Gold Films

Unbacked films of gold 2×${10}^{-6\mathrm{}}$ cm thick were produced and studied to determine their photoelectric behavior. These films did not hold a constant photo-emission, but showed a rapid increase in emission with exposure to ultraviolet light. The increase in photo-current was 136 fold and was accompanied by a shift in long wave limit of 576A. Solid gold and silver were given similar treatment and showed a like effect. This increase is explained on the basis of outgassing caused by ejected electrons removing gas from the surface. The final long wave limit reached by the gold films is compared with that for the mass metal when outgassed by severe heat treatment.