Third Harmonic Characterization of Antiferromagnetic Heterostructures

Abstract

Electrical switching of antiferromagnets is an exciting recent development in spintronics, which promises active antiferromagnetic devices with high speed and low energy cost. In this emerging field, there is an active debate about the mechanisms of current-driven switching of antiferromagnets. Harmonic characterization is a powerful tool to quantify current-induced spin-orbit torques and spin Seebeck effect in heavy-metal/ferromagnet systems. However, the harmonic measurement technique has never been verified in antiferromagnetic heterostructures. Here, we report for the first time harmonic measurements in Pt/$\alpha$-Fe${}_2$O${}_3$ bilayers, which are explained by our modeling of higher-order harmonic voltages. As compared with ferromagnetic heterostructures where all current-induced effects appear in the second harmonic signals, the damping-like torque and thermally-induced magnetoelastic effect contributions in Pt/$\alpha$-Fe${}_2$O${}_3$ emerge in the third harmonic voltage. Our results provide a new path to probe the current-induced magnetization dynamics in antiferromagnets, promoting the application of antiferromagnetic spintronic devices.

References in corpus (9)

• Theory of spin Hall magnetoresistance
• Writing and Reading antiferromagnetic Mn${}_2$Au: Néel spin-orbit torques and large anisotropic magnetoresistance
• Spin pumping and spin-transfer torques in antiferromagnets
• Phenomenology of Current-Induced Dynamics in Antiferromagnets
• Negative spin Hall magnetoresistance of Pt on the bulk easy-plane antiferromagnet NiO
• Imaging of current induced Néel vector switching in antiferromagnetic Mn${}_2$Au
• Quantifying Spin-Orbit Torques in Antiferromagnet/Heavy Metal Heterostructures
• Determining complex spin mixing conductance and spin diffusion length from spin pumping experiments in magnetic insulator/heavy metal bilayers
• Theory of Harmonic Hall Responses of Spin-Torque Driven Antiferromagnets

Cited by in corpus (3)

• Intrinsic Nonlinear Hall Detection of the Néel Vector for Two-Dimensional Antiferromagnetic Spintronics
• Unidirectional Spin Hall Magnetoresistance in Antiferromagnetic Heterostructures
• Characterizing Spin-Orbit Torques by Tensorial Spin Hall Magnetoresistance