ANOMALOUS MAGNETORESISTANCE OF NONEQUILIBRIUM EU-TM (CO,MO) ALLOY THIN-FILMS

We studied the magnetization and magnetoresistance ratio (MR) of noneq uilibrium Eu-rich Eu-TM (TM = Co, Mo) alloy thin films prepared by vap our-phase synthesis. We observed that the magnetization curves of the Eu-TM films show an irreversible kink at about 8 T. The longitudinal a nd transverse MR curves of these films also exhibit irreversible posit ive-to-negative change at about 8 and 4 T, respectively, while reversi ble components show only a monotonic decrease. These behaviours are in contrast with the monotonically increasing MR of pure Eu, measured up to 14 T, but are essentially identical to those observed for nonequil ibrium Eu-Fe thin films, implying that the anomaly results from struct ural disorder rather than from the magnetic moments of impurities.