Antiferromagentic resonance detected by DC voltages in MnF$_2$/Pt bilayers

TL;DR

This study demonstrates the detection of antiferromagnetic resonance in MnF₂/Pt bilayers through broadband ferromagnetic resonance experiments, revealing a small magnetic field-dependent contribution likely due to spin pumping.

Contribution

First direct observation of antiferromagnetic resonance via DC voltages in MnF₂/Pt bilayers, combining microwave and electrical measurements to explore spin dynamics.

Findings

Antiferromagnetic resonance reflected in both microwave transmission and DC voltage.

DC voltage largely unaffected by field reversal, indicating rectification/heating effects.

Small magnetic field orientation dependence suggests spin pumping contribution.

Abstract

We performed coplanar waveguide-based broadband ferromagnetic resonance experiments on the antiferromagnetic insulator MnF$_2$, while simultaneously recording the DC voltage arising in a thin platinum film deposited onto the MnF$_2$. The antiferromagnetic resonance is clearly reflected in both the transmission through the waveguide as well as the DC voltage in the Pt strip. The DC voltage remains largely unaffected by field reversal and thus presumably stems from microwave rectification and/or heating effects. However, we identify a small magnetic field orientation dependent contribution, compatible with antiferromagnetic spin pumping theory.