GMR effect due to L1/sub 0/ FePt grains

The giant magnetoresistance (GMR) effect is found in granular FePt-Ag composite films, which arises from the alignment of L1/sub 0/ FePt grains under a magnetic field. The maximum GMR ratio at room temperature is 0.7%, which is much higher than the resistivity enhancement due to the domain wall scattering in highly ordered L1/sub 0/ FePt films.