A lattice model of thermopower in hopping conduction: Application to neutron-doped crystalline germanium

A model for describing hopping thermopower is proposed. Within the model, t he majority and compensating impurities form a simple cubic lattice in a cr ystal matrix. The thermopower associated with hole (electron) hopping over hydrogen-like impurities is calculated with inclusion of their excited stat es. The results of calculations are compared with available experimental da ta on the low-temperature thermopower of Ge : Ga and the specific heat of S i : P in the dielectric region of the insulator-metal transition. (C) 2001 MAIK "Nauka/Interperiodica".