The Analysis of Photoelectric Sensitivity Curves for Clean Metals at Various Temperatures

Abstract

An elementary theory is developed for the effect of temperature on the photoelectric sensitivity of a clean metal near the threshold. It is shown that the results observed by various workers for silver, gold, tantalum, tin, and potassium can be fairly completely accounted for by the effect of the temperature on the number of electrons available for extraction according to the distribution law of Sommerfeld's theory of metals. This is in agreement with the conclusions of Lawrence and Linford based on much less extensive data. A graphical method is given enabling the whole of the observed curves near the threshold for all temperatures to be used in determining the threshold itself thus avoiding an arbitrary extrapolation to zero current. At present the fundamental theory of the effect survives in two forms, both of which are used as alternatives here, with nearly equal success. Until one or the other can be eliminated it is not possible to determine thresholds closer than about 1 percent.