Microwave Spin-Pumping from an Antiferromagnet FeBO3

TL;DR

This paper demonstrates microwave spin pumping from a canted antiferromagnet FeBO3, showing tunable detection of spin currents via inverse spin Hall effect with potential for portable microwave devices.

Contribution

It provides the first combined theoretical and experimental analysis of microwave spin pumping in a canted antiferromagnet FeBO3 with tunable resonance frequencies.

Findings

Achieved microwave spin pumping detection up to 43.5 GHz.

Demonstrated voltage sensitivity near 2.5 microV/W.

Confirmed pure spin current via polarity switching of the inverse spin Hall voltage.

Abstract

Recently, canted antiferromagnets offer great potential for fundamental research and applications due to their unique properties. The presence of the Dzyaloshinskii-Moriya interaction leads to the existence of a weak ferromagnetic moment at room temperature. We study both theoretically and experimentally microwave spin pumping by the quasi-ferromagnetic mode from a canted easy plane antiferromagnet with weak ferromagnetism FeBO3. The conversion of a microwave signal into the constant voltage is realized using the inverse spin Hall effect in an iron borate/heavy metal heterostructure. We use an additional bias magnetic field to selectively tune the resonance frequency of such a microwave detector over a wide range up to 43.5 GHz with potential sensitivity near 2.5 microV/W. We confirm the pure spin current nature by changing polarity of the detected via inverse spin Hall effect voltage by switching the direction of the bias magnetic field. We believe that our results will be useful for the development of highly tunable, portable and sensitive microwave antiferromagnet-based functional devices.