Chemical solution synthesis and ferromagnetic resonance of epitaxial thin films of yttrium iron garnet

Abstract

Cubic Yttrium Iron Garnet (YIG) is a technologically important material due to its excellent magneto-optical properties, high electrical resistivity, and a very narrow ferromagnetic resonance, which makes it particularly suitable for applications in filters and resonators at microwave frequencies. These properties depend on the precise stoichiometry and distribution of Fe${}^{3+}$ ions among the octahedral/tetrahedral sites of a complex structure, which required the use of high-vacuum deposition methods for the fabrication of high-quality YIG thin films. In this paper the authors report the synthesis of nanometer-thick epitaxial films of YIG by a simple water-based chemical method. The films show a long spin relaxation time, comparable to that obtained from high-vacuum physical deposition methods. These results demonstrate that chemical methods can compete to develop nanometer-thick YIG films with the quality required for spintronic devices and other high-frequency applications.