Large Faraday effect in a short wavelength range for disordered zinc ferrite thin films

We have prepared a zinc ferrite (ZnF2O4) thin film 85 nm thick deposited on a silica glass substrate by using a radio frequency sputtering method. Faraday effect measurements have been carried out not only for as-deposited but also for annealed thin films. The thin film annealed at 300 degrees C as well as the as-deposited thin film exhibit a large Faraday rotation angle at a wavelength of around 390 nm. In particular, the thin film annealed at 300 degrees C manifests the largest Faraday effect among the present thin films; the rotation angle of 1.65 degrees/mu m is attained at a wavelength of 386 nm. The thin films 1.08 mu m thick exhibit a large magnetization at room temperature, and the dependence of the magnetization on the external magnetic field is suggestive of a ferrimagnetic behavior. (c) 2006 American Institute of Physics.