Extra-Large Magnetoresistance in Fe/In₂O₃ Granular Film

Nanogranular Fe_0.35/(In₂O₃)_0.65 film with complex magnetic structure were prepared by the rf sputtering method. An extra-large magnetoresistance up to 506% was obtained at 2.2 K, which is two orders of magnitude larger than that obtained at room temperature. This is related to the interaction with the impurities influencing the local magnetization, which is quite different from spin-dependent tunneling effect at room temperature. The interspacing Fe atoms dispersed in the In₂O₃ matrix play an important role in the transportation properties of carriers at low temperature.