Theoretical Proposal for Determining Angular Momentum Compensation in Ferrimagnets

TL;DR

This paper proposes a theoretical method to determine the angular momentum compensation temperature in ferrimagnets using temperature-dependent current switching, supported by simulations and a Curie-Weiss theory explanation.

Contribution

It introduces a novel theoretical approach based on symmetry reversal in current switching to identify TMC and TAMC in ferrimagnets, supported by a modified Landau-Lifshitz-Bloch model.

Findings

Symmetry reversals at TMC and TAMC enable their identification.

Numerical simulations support the proposed method.

Linear relation between TAMC and TMC explained by Curie-Weiss theory.

Abstract

This work demonstrates that the magnetization and angular momentum compensation temperature (TMC and TAMC) in ferrimagnets (FiM) can be unambiguously determined by performing two sets of temperature dependent current switching, with the symmetry reverses at TMC and TAMC, respectively. A theoretical model based on the modified Landau-Lifshitz-Bloch equation is developed to systematically study the spin torque effect under different temperatures, and numerical simulations are performed to corroborate our proposal. Furthermore, we demonstrate that the recently reported linear relation between TAMC and TMC can be explained using the Curie-Weiss theory.