Direct visualization of current-induced spin accumulation in topological insulators.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 29950680.
- Also identified by DOI 10.1038/s41467-018-04939-6 and PMC identifier 6021425.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Charge-to-spin conversion in various materials is the key for the fundamental understanding of spin-orbitronics and efficient magnetization manipulation. Here we report the direct spatial imaging of current-induced spin accumulation at the channel edges of Bi<sub>2</sub>Se<sub>3</sub> and BiSbTeSe<sub>2</sub> topological insulators as well as Pt by a scanning photovoltage microscope at room temperature. The spin polarization is along the out-of-plane direction with opposite signs for the two channel edges. The accumulated spin direction reverses sign upon changing the current direction and the detected spin signal shows a linear dependence on the magnitude of currents, indicating that our observed phenomena are current-induced effects. The spin Hall angle of Bi<sub>2</sub>Se<sub>3</sub>, BiSbTeSe<sub>2</sub>, and Pt is determined to be 0.0085, 0.0616, and 0.0085, respectively. Our results open up the possibility of optically detecting the current-induced spin accumulations, and thus point towards a better understanding of the interaction between spins and circularly polarized light.