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Fe/In multilayers were prepared by the DC magnetron sputtering method, and their electrical and magnetic properties were studied. Negative giant magnetoresistance (GMR) with a maximum of −0.84% at 10 K was observed. The magnitude of GMR and the saturation field ( H s ) were found to oscillate with a period about 1.3 nm when varying the thickness of In layers. Atomic force microscope images of samples were taken to investigate the surface morphology. The GMR effect is composed of antiferromagnetic coupling between the neighboring Fe layers and superparamagnetic spins effect at the Fe/In interface. A reduction of the anomalous GMR effect with decreasing temperature is presented.

The single crystal Ni54Fe19Ga27 shows a martensitic transformation at 281 K on cooling and 283 K on warming. Large jumps in the temperature-dependent resistance curve, temperature-dependent magnetization curve and temperature-dependent thermal conductivity curve are observed at the martensitic transition temperature (TM). Negative magnetoresistance due to spin disorder scattering was observed in Ni54Fe19Ga27 single crystal in all temperature ranges. The Ni54Fe19Ga27 sample exhibited a temperature dependence of thermal conductivity κ(T)(dκ/dT>0) due to atomic disorder above a temperature of 50 K.