Thermoelectric detection of ferromagnetic resonance of a nanoscale ferromagnet

TL;DR

This paper introduces a thermoelectric method to detect ferromagnetic resonance in nanoscale ferromagnets, which is applicable to both conductive and insulating materials, providing a new tool for magnetic resonance studies.

Contribution

It demonstrates a novel thermoelectric detection technique for ferromagnetic resonance that does not require electrical conductivity of the sample.

Findings

Resonance peak shape matches Landau-Lifshitz-Gilbert predictions.

Thermoelectric detection is effective in both conductive and insulating ferromagnets.

Finite element modeling supports experimental results.

Abstract

We present thermoelectric measurements of the heat dissipated due to ferromagnetic resonance of a Permalloy strip. A microwave magnetic field, produced by an on-chip coplanar strip waveguide, is used to drive the magnetization precession. The generated heat is detected via Seebeck measurements on a thermocouple connected to the ferromagnet. The observed resonance peak shape is in agreement with the Landau-Lifshitz-Gilbert equation and is compared with thermoelectric finite element modeling. Unlike other methods, this technique is not restricted to electrically conductive media and is therefore also applicable to for instance ferromagnetic insulators.