Large Room Temperature Charge-to-Spin Conversion Efficiency in Topological Insulator/CoFeB bilayers

Qiming Shao, Guoqiang Yu, Lei Pan, Xiaoyu Che, Yabin Fan, Koichi Murata, Qing Lin He, Tianxiao Nie, Xufeng Kou, Kang L. Wang

研究成果: Conference contribution

2 引文 斯高帕斯(Scopus)


Heavy metals and topological insulators are promising materials for converting charge current into spin current for efficient manipulation of magnetization states in magnetic devices [1]-[5]. One of the most important parameters is the charge-to-spin conversion (CS) efficiency. Improving CS efficiency is critical for reducing write current of the emerging nonvolatile memory technology, spin-orbit torque MRAM (SOT-MRAM) [2], which provides comparable speed with SRAM but with a much higher memory capacity. Here, we measure CS efficiency in various topological insulators (TIs) using second-harmonic method (2eo-method) and obtain a record-high value 8.33±0.65 for insulating (BiSb)2 Te3 at room temperature. We first establish the consistency of CS efficiency obtained between spin-torque ferromagnetic resonance (ST-FMR) and 2eo-method. Then, we systematically investigate the CS efficiency in a bilayer consisting of a metallic Bi2Se3 and a CoFeB thin film using 2eo-method. By tuning the Fermi level of TI layer into bulk band gap using (BiSb)2Te3, we improve the CS efficiency by an order of magnitude.

主出版物標題2018 76th Device Research Conference, DRC 2018
發行者Institute of Electrical and Electronics Engineers Inc.
出版狀態Published - 2018 八月 20
事件76th Device Research Conference, DRC 2018 - Santa Barbara, United States
持續時間: 2018 六月 242018 六月 27


名字Device Research Conference - Conference Digest, DRC


Conference76th Device Research Conference, DRC 2018
國家/地區United States
城市Santa Barbara

All Science Journal Classification (ASJC) codes

  • 電氣與電子工程


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