Magneto-Optical Properties of Co Doped Bi3Fe5O12 Garnet Film

Abstract

AbstractCo-doped Bi3Fe5O12 garnet (BIG) films were prepared on Gd3(ScGa)5O12(GSGG) substrates using two types of ion-beam-sputtering (IBS) technique. In the films deposited by sputtering the Co and the BIG source targets alternately with short periodicity, the interface exchange coupling of BIG and Co-spinel ferrite was characteristically observed in the Faraday hysteresis loop. The magnetic and the Faraday hysteresis loops were found to have different coercivity. In the films deposited by conventional IBS method using the BIG target doubly substituted by Co and Ge, Co2+ ions were highly replaced up to 0.7 atoms/formula unit for Fe3+ in BIG. The specific Faraday rotation angle (θ F) at a wavelength of 1.5 μ m was 1.1 deg/μm/Co atom. The magnetic easy direction was normal to the film plane.