EFFECTS OF LOW-LYING DYNAMIC EXCITATIONS ON THE THERMOPOWER OF AMORPHOUS METALS

We report on experimental and theoretical results on thermopower. This contributes to the old-standing problem that in disordered metals the thermopower very often shows at elevated temperatures the opposite si gn in comparison to the Hall coefficient. Liquid and amorphous materia ls show characteristic low-lying anomalies in their phonon dispersion at scattering vectors K where the static structure factor shows a peak . Since in many glassy metals 2k(F) is located at the same K-value, su bsequently, the electrons may suffer strong elastic umklapp-scattering effects with the static structure and as well a strong inelastic umkl app scattering with the low-lying phonon anomalies. Versus temperature the inelastic part changes drastically and the thermopower switches f rom a negative to a positive value.