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arXiv · 1511.07442

Electric-field control of spin-orbit torque in a magnetically doped topological insulator

Yabin Fan·Xufeng Kou·Pramey Upadhyaya·Qiming Shao·Lei Pan·Murong Lang·Xiaoyu Che·Jianshi Tang·Mohammad Montazeri·Koichi Murata·Li-Te Chang·Mustafa Akyol·Guoqiang Yu·Tianxiao Nie·Kin L. Wong·Jun Liu·Yong Wang·Yaroslav Tserkovnyak·Kang L. Wang
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Abstract

Electric-field manipulation of magnetic order has proved of both fundamental and technological importance in spintronic devices. So far, electric-field control of ferromagnetism, magnetization and magnetic anisotropy has been explored in various magnetic materials, but the efficient electric-field control of spin-orbit torque (SOT) still remains elusive. Here, we report the effective electric-field control of a giant SOT in a Cr-doped topological insulator (TI) thin film using a top-gate FET structure. The SOT strength can be modulated by a factor of 4 within the accessible gate voltage range, and it shows strong correlation with the spin-polarized surface current in the film. Furthermore, we demonstrate the magnetization switching by scanning gate voltage with constant current and in-plane magnetic field applied in the film. The effective electric-field control of SOT and the giant spin-torque efficiency in Cr-doped TI may lead to the development of energy-efficient gate-controlled spin-torque devices compatible with modern field-effect semiconductor technologies.

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Yabin Fan, Xufeng Kou, Pramey Upadhyaya, Qiming Shao, Lei Pan, Murong Lang, Xiaoyu Che, Jianshi Tang, Mohammad Montazeri, Koichi Murata, Li-Te Chang, Mustafa Akyol, Guoqiang Yu, Tianxiao Nie, Kin L. Wong, Jun Liu, Yong Wang, Yaroslav Tserkovnyak, Kang L. Wang. 2015-11-23. Electric-field control of spin-orbit torque in a magnetically doped topological insulator. https://doi.org/10.1038/nnano.2015.294

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