Anomalous magnetoresistivity of amorphous GdCo3 thin films

Abstract

Magnetoresistance and Hall effect in amorphous ferrimagnetic GdCo3 thin films have been measured over a temperature range from 1.5 to 320 K and in magnetic fields up to 70 kOe. Beyond technical saturation, the magnetoresistance is positive, isotropic, varies linearly with the applied field, and up to 50 K is temperature independent. Possible contributions are discussed in detail. In particular, Coulomb interaction theories may account for the positive high-field slope, provided the magnetic moment of the Co sublattice is exchange enhanced by that of the Gd sublattice in the applied field.