Magnetothermopower of aAg80Co20granular system

A large magnetothermopower (MTP) has been found to accompany the magnetoresistance (MR) in a ${\mathrm{Ag}}_{80}$ ${\mathrm{Co}}_{20}$ granular system. The zero-field thermopower is negative and its magnitude increases as the magnetic field increases. The MTP is inversely proportional to the resistance in the temperature range where the diffusion thermopower dominates. These observations support the spin-split density-of-states (DOS) model which yields both the MTP and the MR for multilayers and granular systems, even with a spin-independent potential at the interfaces.