Magneto-optical properties of Y2BiFe5O12/Bi2 Sr2CaCu2O8+x/SrTiO3 structures

Deposition of magneto-optical film directly on superconducting layer has been studied in order to improve the spatial resolution and the magnetic sensitivity in a magneto-optical (MO) imaging of single vortices. Calculation of MO effect in Y2BiFe5O12 (Bi:YIG)/Bi2Sr2CaCu2O8+x (BSCCO)/SrTiO3 (STO) structure was carried out using the virtual optical constant method between 2 and 3 eV, showing possibility of enhancement of Kerr rotation up to approximately 4° for a thin Bi:YIG film of 200 nm in thickness. Preparation of the Bi:YIG/BSCCO/STO structures with an optimum layer thickness determined by the simulation was carried out by using the metal-organic decomposition (MOD) method. However only a small Kerr rotation was realized, suggesting degradation of magneto-optical effect due to out-diffusion of Bi.