Significant Unconventional Anomalous Hall Effect in Heavy Metal/Antiferromagnetic Insulator Heterostructures

Abstract

The anomalous Hall effect (AHE) is a quantum coherent transport phenomenon that conventionally vanishes at elevated temperatures because of thermal dephasing. Therefore, it is puzzling that the AHE can survive in heavy metal (HM)/antiferromagnetic (AFM) insulator (AFMI) heterostructures at high temperatures yet disappears at low temperatures. In this paper, we report that an unconventional high-temperature AHE in HM/AFMI is observed only around the Néel temperature of AFM, with large anomalous Hall resistivity up to 40 n$\Omega$ cm. This mechanism is attributed to the emergence of a noncollinear AFM spin texture with a non-zero net topological charge. Atomistic spin dynamics simulation shows that such a unique spin texture can be stabilized by the subtle interplay among the collinear AFM exchange coupling, interfacial Dyzaloshinski-Moriya interaction, thermal fluctuation, and bias magnetic field.

References in corpus (8)

• Theory of spin Hall magnetoresistance
• Spin pumping and spin-transfer torques in antiferromagnets
• Subterahertz spin pumping from an insulating antiferromagnet
• Topological Hall effect at above room temperature in heterostructures composed of a magnetic insulator and a heavy metal
• Probing Magnetism in Insulating Cr2Ge2Te6 by Induced Anomalous Hall Effect in Pt
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• Significant Unconventional Anomalous Hall Effect in Heavy Metal/Antiferromagnetic Insulator Heterostructures

Cited by in corpus (2)

• Significant Unconventional Anomalous Hall Effect in Heavy Metal/Antiferromagnetic Insulator Heterostructures
• Electrical Modulation and Probing of Antiferromagnetism in Hybrid Multiferroic Heterostructures