Thermally controlled confinement of spin wave field in a magnonic YIG waveguide

TL;DR

This paper demonstrates that the electrodynamical coupling between spin waves and probes in a YIG waveguide is temperature-dependent, leading to thermal control of spin wave field confinement, which impacts spin wave detection techniques.

Contribution

It provides the first experimental and theoretical evidence of temperature-dependent spin wave field confinement in a magnonic YIG waveguide.

Findings

Coupling strength varies with temperature and distance.

Thermal confinement occurs near the YIG-Air interface.

Results are relevant for spin wave detection and caloritronics.

Abstract

Methods for detecting spin waves rely on electrodynamical coupling between the spin wave dipolar field and an inductive probe. While this coupling is usually treated as constant, in this work, we experimentally and theoretically show that it is indeed temperature dependent. By measuring the spin wave magnetic field as a function of temperature of, and distance to the sample, we demonstrate that there is both a longitudinal and transversal confinement of the field near the YIG-Air interface. Our results are relevant for spin wave detection, in particular in the field of spin wave caloritronics