Nonlinear Absorption of Radio Waves in a Noncollinear Antiferromagnet

TL;DR

This study investigates how radio waves are nonlinearly absorbed in a noncollinear cubic antiferromagnet, revealing energy dissipation through parametric excitation of surface waves at low temperatures.

Contribution

It provides new insights into the nonlinear radio wave absorption mechanisms in noncollinear antiferromagnets under magnetic fields.

Findings

Nonlinear absorption observed in 200-800 MHz range.

Energy dissipation linked to surface wave excitation.

Effect prominent at low temperatures (1.2-4.2 K).

Abstract

The nonlinear absorption of radio waves (200 - 800 MHz) in a noncollinear cubic antiferromagnet Mn3Al2Ge3O12 in an external magnetic field H || [001] has been studied in the temperature range of 1.2 - 4.2 K. We attribute the observed dissipation of the electromagnetic energy to the parametric excitation of inhomogeneous surface waves at the boundaries of antiferromagnetic domains.