Hall Effect for Electrons in Silver Chloride

Abstract

The Hall mobility of photoelectrons has been measured down to 5°K in single crystals of silver chloride. The experiment was carried out with a pulse technique which overcomes the difficulties of space charge and high impedance common to such measurements on insulating crystals. Results show that the electron Hall mobility rises to high values, 6000 ${\mathrm{cm}}^2$/volt-sec. at very low temperature. On the other hand, drift mobility is strongly influenced by multiple trapping and is not characteristic of microscopic mobility in these crystals at low temperature. Comparison with mobility theory indicates that electrons are scattered by both the optical and acoustical modes of lattice vibration depending upon the range of temperature. Evidence for a structure-dependent scattering such as would be produced by impurities is found below 20°K. Magnetoresistance effects begin to become important at high values of mobility and magnetic field in qualitative agreement with the theory of electronic conductivity for a cubic crystal with simple energy bands and nondegenerate statistics.