Effects of light-irradiation on spin-glass state and magnetoresistive properties of Zn0.5Co0.5Fe2O4 spinel ferrite films

Spin-glass spinel ferrite Zn0.5Co0.5Fe2O4 films were prepared on α-Al2O3(0001) substrates and the effect of light-irradiation on the spin-glass state was studied. The magnetization of prepared films showed a broad maximum at 260 K in a zero-field-cooled (ZFC) process, which is characteristic of a spin glass or a cluster glass. When shining light on the film under H=1 kOe, the magnetization in the ZFC process increased, and returned to its original level when the light was turned off. This switching behavior was confirmed to work even at 350 K. magnetoresistance (MR) and photo-induced MR effects of this film are also described.