Theory of magnetic inertial dynamics in two-sublattice ferromagnets

TL;DR

This paper develops a theoretical framework for magnetic inertial dynamics in two-sublattice ferromagnets, deriving susceptibility and resonance frequencies, revealing contrasting effects of intra- and inter-sublattice inertial dynamics.

Contribution

It introduces a comprehensive model for inertial effects in two-sublattice ferromagnets, extending previous single-sublattice theories.

Findings

Resonance frequencies decrease with intra-sublattice relaxation time.

Inter-sublattice inertial dynamics have contrasting effects.

Derived magnetic susceptibility for two-sublattice ferromagnets.

Abstract

The magnetic inertial dynamics have been investigated for one sublattice ferromagnets. Here, we develop the magnetization dynamics in two-sublattice ferromagnets including the intra- and inter-sublattice inertial dynamics. First, we derive the magnetic susceptibility of such a ferromagnet. Next, by finding the poles of the susceptibility, we calculate the precession and nutation resonance frequencies. Our results suggest that while the resonance frequencies show decreasing behavior with the increasing intra-sublattice relaxation time, the effect of inter-sublattice inertial dynamics is contrasting.