Control of a ferrimagnet phase by a two-component magnetic field

We report a theoretical study of the phase diagram of a ferrimagnetic iron-garnet with uniaxial anisotropy near a magnetization compensation point in the presence of a two-component magnetic field. The study is performed based on a quasi-antiferromagnetic approximation. The number and stability of the equilibrium states of the Neel vector are analyzed using the effective energy function. It is shown that application of the small out-of-plane magnetic field in addition to the stronger in-plane magnetic field significantly changes the equilibrium states of a ferrimagnet. The possibilities to control the equilibrium Neel vector position and to switch between the monostable and bistable states by tuning the value and ratio of the in-plane and out-of-plane magnetic field components are demonstrated. This opens new possibilities for the utilization of ferrimagnets since the magnetic field could be changed much faster than the temperature.