Nutation resonance in different states of an antiferromagnet switched by an external magnetic field

The results of the study of nutation resonances caused by the magnetization inertia of an antiferromagnet with two sublattices, possessing uniaxial magnetocrystalline anisotropy, are presented. Analytical expressions for the eigenfrequencies of the antiferromagnet are obtained by linearizing the system of coupled inertial Landau–Lifshitz–Gilbert equations describing the dynamics of the sublattice magnetizations. Various states of the antiferromagnet determined by the magnitude of the external magnetic field are considered for longitudinal (along the easy axis) and transverse directions of the field. The effect of dissipation in the system on the half-widths of the nutation resonance lines is demonstrated.