The Giant Spin-to-Charge Conversion of the Layered Rashba Material BiTeI

Li Cai; Chenglin Yu; Wenxuan Zhao; Yong Li; Hongmei Feng; Heng-An Zhou; Ledong Wang; Xiaofang Zhang; Ying Zhang; Youguo Shi; Jinsong Zhang; Lexian Yang; Wanjun Jiang

doi:10.1021/acs.nanolett.2c02354

The Giant Spin-to-Charge Conversion of the Layered Rashba Material BiTeI

Nano Lett. 2022 Sep 28;22(18):7441-7448. doi: 10.1021/acs.nanolett.2c02354. Epub 2022 Sep 13.

Authors

Li Cai^{1

2

3}, Chenglin Yu^{1

2

3}, Wenxuan Zhao^{1

2

3}, Yong Li⁴, Hongmei Feng^{1

2

3}, Heng-An Zhou^{1

2

3}, Ledong Wang^{1

2

3}, Xiaofang Zhang⁵, Ying Zhang^{4

5}, Youguo Shi⁴, Jinsong Zhang^{1

2

3}, Lexian Yang^{1

2

3}, Wanjun Jiang^{1

2

3}

Affiliations

¹ State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China.
² Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China.
³ Collaborative Innovation Center of Quantum Matter, Beijing 100084, China.
⁴ Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
⁵ Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China.

PMID: 36099337
DOI: 10.1021/acs.nanolett.2c02354

Abstract

Rashba spin-orbit coupling (SOC) could facilitate an efficient interconversion between spin and charge currents. Among various systems, BiTeI holds one of the largest Rashba-type spin splittings. Unlike other Rashba systems (e.g., Bi/Ag and Bi₂Se₃), an experimental investigation of the spin-to-charge interconversion in BiTeI remains to be explored. Through performing an angle-resolved photoemission spectroscopy (ARPES) measurement, such a large Rashba-type spin splitting with a Rashba parameter α_R = 3.68 eV Å is directly identified. By studying the spin pumping effect in the BiTeI/NiFe bilayer, we reveal a very large inverse Rashba-Edelstein length λ_IREE ≈ 1.92 nm of BiTeI at room temperature. Furthermore, the λ_IREE monotonously increases to 5.00 nm at 60 K, indicating an enhanced Rashba SOC at low temperature. These results suggest that BiTeI films with the giant Rashba SOC are promising for achieving efficient spin-to-charge interconversion, which could be implemented for building low-power-consumption spin-orbitronic devices.

Keywords: 2D material; ARPES; BiTeI; Rashba SOC; spin pumping.