Antiferromagnetic Resonance

a kind of electron magnetic resonance. Antiferromagnetic resonance manifests itself as a sharp rise in the absorption of electromagnetic energy passing through antiferromagnetic material for certain (resonant) values of the frequency v and of the intensity of the applied magnetic field H. Antiferromagnetic materials typically have an ordered arrangement of magnetic moments for the atoms (ions). Elementary magnetic moments having the same orientation in antiferromagnetic materials form so-called sublattices (two in the simplest case). In antiferromagnetic resonance resonant vibrations are excited in the magnetization vectors of the sublattices with respect both to one another and to the direction of the applied field H. The form of the dependence of v on the effective magnetic fields in antiferromagnetic materials is very complicated and varies for different crystal structures. As a rule, a single value of an applied field corresponds to two antiferromagnetic resonance frequencies. Antiferromagnetic resonance frequencies lie in the range of 10 to 1000 gigahertz.

A study of antiferromagnetic resonance permits the values of the effective magnetic fields to be determined in an antiferromagnetic material.