Thermoelectric transport properties in disordered systems near the Anderson transition

We study the thermoelectric transport properties in the three-dimensional Anderson model of localization near the metal-insulator transition (MIT). In particular, we investigate the dependence of the thermoelectric power S, the thermal conductivity K, and the Lorenz number L-0 on temperature T. We first calculate the T dependence of the chemical potential mu from the number density n of electrons at the MIT using an averaged density of states obtained by diagonalization. Without any additional approximation, we determine from mu(T) the behavior of S, K and Lo at low T as the MIT is approached. S;Ve find tl-lat a and K decrease to aero at the MIT as T --> 0 and show that S does not diverge. Both S and Lo become temperature independent at the MIT and depend only on the critical behavior of the conductivity.