Nanometer-thick Ga/Al substituted yttrium iron garnet ultra-thin films by liquid phase epitaxial method

Abstract In microwave and spintronic applications, the Gilbert damping coefficient and ferromagnetic resonance (FMR) line width play a decisive role in the component losses. Yttrium iron garnet (YIG) film is a good candidate due to the extremely small damping factor. 4.8 and 51.3 nm ultra-thin Y 3 (GaAlFe) 5 O 12 (GaAl-YIG) films are grown on gadolinium gallium garnet (GGG) substrate using liquid phase epitaxial (LPE) technology. The films show a (111) orientation and tensile strain, and the roughness of the film surface is small. The films show a low saturation magnetization because of Ga and Al substituted, and the comparison of magnetization properties with film thickness is analyzed. The FMR line width is tested, and the calculated damping constant of the 51.3 nm film is on the order of 10 −4 . The structural and magnetization properties analysis demonstrates that LPE technology has the potential to provide nanometer-thick garnet films for low-loss spintronic devices.