Modeling of external influence on the resonance properties of bulk antiferromagnet α − Fe2O3 during a spin-reorientation transition

Abstract

This paper presents a model that explains the influence of external pressure on the resonant frequency of a bulk crystal a–Fe2O3 in an external magnetic field. The dynamics of vectors l and m before and after the Morin temperature TM are considered. The dependences of the resonant frequency on pressure and external magnetic field for the cases H║(HA ║ z) and H┴(HA ║ z) are obtained, and the dependences of the magnetic field on pressure are obtained for the lower and upper modes. It was found that when external pressure is applied to the structure, the natural frequency of vibrations of the magnetic sublattices of the antiferromagnet increases significantly. The results obtained can be used in the development of devices for generating and processing signals in the gigahertz and terahertz frequency ranges.