Anomalous temperature-dependent magnetization of Ni films on semiconductorsubstrates

Magnetization, M(T, H = const.) and M(H, T = const.), of Ni films deposited on n-GaAs(1 0 0) and Si(1 0 0) substrates has been performed in magnetic f ields both parallel and perpendicular to the film plane. The unsaturated mo ment of Ni films on n-GaAs substrate around the hysteresis exhibits an anom alous magnetization with temperature in parallel field. In perpendicular fi eld this effect disappears but an undulated hysteresis curve has been obser ved. Similar Ni films on Si substrate do not exhibit any remarkable anomaly . The effect is likely to originate from the interface of Ni and GaAs. (C) 2001 Elsevier Science B.V. All rights reserved.