Electrical resistivity, thermal conductivity, and thermopower in the U=

Abstract

Electrical resistivity, thermal conductivity, and thermopower in the single-band, U=\ensuremath{\infty}, Hubbard model near half-filling are studied by using the retraceable-path approximation originally developed by Brinkman and Rice. We find that the electrical resistivity is proportional to T in the wide temperature range T\ensuremath{\gtrsim}t, where T and t are the temperature and the nearest-neighbor hopping integral, respectively. The thermal conductivity becomes a maximum at T\ensuremath{\sim}t. The thermopower is positive and large at high temperatures, and it has very weak temperature dependence at T\ensuremath{\gtrsim}t. In this context, the Lorenz number decreases with increasing temperature. The magnetoresistance due to orbital motion of holes is also discussed.