Magnetoresistance anomalies in the Gd-based alloys

Abstract

The magnetoresistance (Δρ/ρ) behavior across magnetic ordering temperatures in the Gd alloys, GdCu₂Si₂, Gd_1−xY_xNi₂Si₂, GdPt₂Si₂, and GdPd₂In, is presented. In all of these alloys, except GdCu₂Si₂, Δρ/ρ is negative in the paramagnetic state and its magnitude grows as the respective magnetic ordering temperatures are approached. On the other hand, Δρ/ρ is positive in the case of GdCu₂Si₂ both above and below the Néel temperature. The findings noted for the Gd alloys containing Ni, Pt, and Pd are interesting, presumably arising from spin fluctuations from the transition-metal d bands.