Absolute thermoelectric power in ferromagnetic amorphous Fe_xNi_80-xB₂₀ alloys

Abstract

The absolute thermoelectric power (TEP), S, as a function of temperature has been measured for amorphous Fe_xNi_80-xB₂₀ alloys (10≤x≤80) in the temperature range 4.2-300 K. A detailed analysis of S(T) data establishes that the nonlinear TEP variation in magnetic glasses is basically due to the dominant contribution to TEP arising from magnetic scattering of conduction electrons from magnetic atoms for T≤T_c. An attempt to find a suitable explanation of the TEP results in terms of the available theoretical models reveals that, although both Mott s-d scattering and Herzer models can provide a qualitative explanation for certain features of S(T,x) behavior, a quantitative agreement between theory and experiment can only be achieved when unphysical values of the electronic and magnetic parameters, appearing in the theoretical expressions for S, are used.