Some Electrical and Optical Properties of Synthetic Single Crystals of Zinc Sulfide

The fundamental optical absorption edge and the temperature dependence of electrical conductivity of synthetic single crystals of hexagonal zinc sulfide have been measured, as well as the photoconductivity near the absorption edge. The fundamental absorption coefficient is 1 ${\mathrm{mm}}^{-1\mathrm{}}$ at a photon energy of (3.58±0.02) ev and increases exponentially by a factor of ten every 0.07 ev up to ${10}^3$ ${\mathrm{mm}}^{-1\mathrm{}}$. The logarithm of the electric resistivity varies linearly as a function of the inverse absolute temperature with a slope of (3.77±0.1) ev/2k. A peak in the spectral variation of photoconductivity has been observed at the optical absorption edge.