MECHANISMS OF ELECTRON-PHONON RELAXATION IN THERMO-EMF AND MAGNETOTHERMO-EMF OF AL AND IN AT LOW-TEMPERATURES

On the basis of experimental results for high-purity Al and literature data for In, it is shown that for a noncompensated polyvalent metal w ith a closed Fermi surface described by a weak pseudopotential, the th ermo-emf and magnetothermo-emf at low temperatures are, according to t he diffusion theory, determined by two competing contributions. One of them is connected with the thermal electron diffusion and the phonon entrainment in N-processes; it may be expressed in terms of the electr on and lattice heat capacity of the crystal and varies in the magnetic field similarly to the Hall (Rigi-Ledyuk) coefficient. The other is d ue to the phonon entrainment in U-processes this may be expressed thro ugh the components of the magnetoresistance tenser and contains the Pe ierls exponent at T < T-0.