MECHANISMS OF ELECTRON-PHONON RELAXATION IN THERMO-EMF AND MAGNETOTHERMO-EMF OF NONCOMPENSATED POLYVALENT METALS WITH CLOSED FERMI-SURFACE

A theory of thermo-emf of noncompensated polyvalent metals with the cl osed Fermi surface which can be described by a weak pseudopotential wh en the small-angle electron-phonon scattering predominates is develope d. The phonon entrainment of the electrons and the Umklapp processes a re comprehensively taken into account. A qualitative explanation is gi ven to the significant experimental discrepancy between the temperatur e dependences of the thermo-emf in Al and In at H = 0. It is shown tha t in the magnetic field H the thermoemf S is dictated by the-competiti on between the two contributions S(C) and S(U). The first contribution is connected with the thermal diffusion and the electron entrainment by the phonon wind in the N-processes and can be calculated through th e electron and phonon heat capacity of the crystal, the other one is e xpressed via the components of the tensor of the resistance in the mag netic field ard is due to the electron entrainment by the phonon wind in the U-processes.