Low-temperature magnetic effects of nanometer Fe-In₂O₃ granular films

Nanometer Fe-In₂O₃ granular films were fabricated by radio frequency sputtering- The particular magnetic effects, which are the giant magnetoresistance effect and the magnetic relaxation effect, of the granular films at low temperature have been studied. The measuring results of magnetoresistance show that the magnetoresistance ratio Δρ/ρ₀ value of the granular films sample with Fe volume percent of 35% is 4.5% at room temperature, and when T = 2 K, Δρ/ρ₀ value reaches 85%. According to the dependence of low field susceptibility on temperature, it was found that the nanometer-sized Fe particles in granular films showed the magnetic relaxation effect at definite temperature. The magnetic property of granular films changes from super-paramagnetic into ferromagnetic at the blocking temperature TB = 50 K. Above the blocking temperature.