INFLUENCE OF A MAGNETIC FIELD ON HOPPING CONDUCTING IN p-TYPE GERMANIUM.

Investigation was made of the influence of a longitudinal magnetic field (up to 60 kOe) on the hopping resistivity of p-type Ge samples with different concentrations of the principal impurity N but with a constant compensation ratio K equals 0. 40. The influence of the magnetic field on the activation energy of hopping conduction epsilon //3 was considered separately from the influence on the preexponential factor rho //3. An expression was obtained for the dependence of epsilon //3 on N**1**/**3 for K equals 0. 40 without allowance for the broadening of levels of isolated impurities and for the formation of an impurity band. The magnetoresistance of more heavily doped samples appeared because their conductivity was proportional to the width of the impurity band. Further increase in the impurity concentration gave rise to a minimum in the dependence of the magnetoresistance on N. This minimum corresponded to an impurity concentration above which the motion of carriers in the impurity band could be described in terms of the mobility.