Some Semimetallic Characteristics of the Photoelectric Emission from As, Sb, and Bi

Abstract

Spectral and energy distributions were determined for photoelectrons from crystalline evaporated layers of As, Sb, and Bi. The relative numbers of electrons ejected from states near the Fermi level were obtained by the method of interchangeable emitters. In each case, the result was several times smaller than that expected for a simple metal. Structure was observed in the energy distribution function $N(\nu ,E)$ for Sb. These effects were attributed qualitatively to an overlapping of energy bands like that assumed in the conventional model for semimetals. Data could be analyzed conveniently with the aid of the function $\frac{N(\nu ,E)}{E}$ previously applied to semiconductors. Spectral distributions, relatively insensitive in form to deviations from metallic behavior, could be fitted by Fowler plots. Work functions so determined differed by less than 0.1 ev from the following values derived from energy measurements: As, 4.72 ev; Sb, 4.60; Bi, 4.34.