Garnet multilayer thin film structure with magnetostatically-altered and improved magnetic properties prepared by RF magnetron sputtering

We prepare an all-garnet multilayer film structure by sandwiching a magneto-soft garnet material in between two magneto-hard garnet materials with high bismuth substitution levels using RF magnetron sputtering technique and investigate the microstructure and the effects of magnetostatic inter-layer coupling on magnetic properties. Both types of the Bi-substituted magneto-optic garnet materials used possess excellent optical, magnetic and magneto-optical properties suitable for the application in different new and emerging technologies in optics and photonics. Garnet layers of composition type Bi₂Dy₁Fe₄Ga₁O₁₂ have strong perpendicular magnetic anisotropy and Bi_1.8Lu_1.2Fe_3.6Al_1.4O₁₂ magneto-soft layer features magnetization behavior similar to that of in-plane magnetized films. The all-garnet magnetostatically-coupled multilayer structure fabricated demonstrates an attractive combination of low coercive force and high uniaxial magnetic anisotropy, which is extremely useful for applications in nanophotonics, optical sensors and isolators.