Abstract
Previous theories of impurity bands in a magnetic field by the authors are extended to give a full account of the galvanomagnetic transport coefficients for the system so far introduced. The formulas for three basic components of the conductivity tensor σxx, σxy and σzz derived here are such that (1) single-site scatterings are taken into account in the one-particle and two-particle Green functions all the way self-consistently, (2) they are applicable both to the intrinsic band and the impurity band simultaneously, and (3) they are applicable to any magnetic field strength. One characteristic point clarified is a reduction of the high-field Hall conductivity σxy in the impurity band region, reflecting a localized nature of the impurity band electrons. This fact is demonstrated by performing an integration involving the Fermistatistics in the expressions of the conductivities and comparing the temperature dependence of σxy with that of σxx. This provides a clear-cut theoretical confirmation that the high-field galvanomagnetic effects is InSb reported by Miyazawa (J. Phys. Soc. Japan 26 (1969), 700) is in fact originated in the proposed impurity band conduction.
