α-Fe₂O₃外延薄膜中三态反铁磁奈尔序的电开关效应

Electrical Switching of Tristate Antiferromagnetic Néel Order in α-Fe_{2}O_{3} Epitaxial Films.

作者信息

Cheng Yang, Yu Sisheng, Zhu Menglin, Hwang Jinwoo, Yang Fengyuan

机构信息

Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.

Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio 43212, USA.

出版信息

Phys Rev Lett. 2020 Jan 17;124(2):027202. doi: 10.1103/PhysRevLett.124.027202.

DOI:10.1103/PhysRevLett.124.027202

PMID:32004028

Abstract

We demonstrate nondecaying, steplike electrical switching of tristate Néel order in Pt/α-Fe_{2}O_{3} bilayers detected by the spin-Hall induced anomalous Hall effect. The as-grown Pt/α-Fe_{2}O_{3} bilayers exhibit sawtooth switching behavior generated by current pulses. After annealing by a high pulse current, the Hall signals reveal single-pulse saturated, nondecaying, steplike switching. Together with control experiments, we show that the sawtooth switching is due to an artifact of Pt while the actual spin-orbit torque induced antiferromagnetic switching is steplike. Our Monte Carlo simulations explain the switching behavior of α-Fe_{2}O_{3} Néel order among three in-plane easy axes.

摘要

我们通过自旋霍尔诱导反常霍尔效应检测到，在Pt/α-Fe₂O₃双层膜中呈现出三态奈尔序的非衰减、阶梯状电开关特性。生长态的Pt/α-Fe₂O₃双层膜表现出由电流脉冲产生的锯齿状开关行为。经过高脉冲电流退火后，霍尔信号呈现单脉冲饱和、非衰减、阶梯状开关特性。结合对照实验，我们表明锯齿状开关是由于Pt的假象，而实际的自旋轨道扭矩诱导的反铁磁开关是阶梯状的。我们的蒙特卡罗模拟解释了α-Fe₂O₃奈尔序在三个面内易轴之间的开关行为。