The Connection between Spin Wave Polarization and Dissipation

TL;DR

This paper reveals a universal link between spin wave polarization and dissipation, showing that dissipation rates are scaled by polarization and applicable across various magnetic systems, enhancing understanding of spin wave dynamics.

Contribution

It introduces a fundamental theoretical connection between spin wave polarization and dissipation, validated through numerical analysis, applicable across diverse magnetic interactions.

Findings

Dissipation rate exceeds Gilbert damping by polarization-dependent factor.

Universal connection applies across different magnetic textures.

Provides new insights into spin wave dynamics and energy loss.

Abstract

This study establishes a fundamental connection between the dissipation and polarization of spin waves, which are often treated as independent phenomena. Through theoretical analysis and numerical validation, we demonstrate that within the linearized spin wave regime, a spin wave mode's dissipation rate, defined as the ratio of linewidth to the resonance frequency, exceeds Gilbert damping by a factor given by its spatially averaged polarization. This average is governed by a non-positive definite weight, whose magnitude depends on the magnon density of the local excitation, while its sign is dictated by the local polarization handedness. Remarkably, this universal connection applies across diverse magnetic interactions and textures, offering crucial insights into spin wave dynamics and dissipation.