Influence of Metal Interlayers on Spin-Charge Conversion in Sb<sub>2</sub>Te<sub>3</sub> Topological Insulator-Based Devices.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40249854.
- Also identified by DOI 10.1021/acs.nanolett.4c06658 and PMC identifier 12046589.
- 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
The magnetization of a ferromagnetic layer can be controlled via spin-charge conversion (SCC) phenomena originating in an adjacent topological insulator (TI). Insertion of nonmagnetic interlayers between these materials has been demonstrated to enhance the SCC efficiency, as shown for Sb<sub>2</sub>Te<sub>3</sub>/Au/Co(Fe) heterostructures. The inert nature of the Sb<sub>2</sub>Te<sub>3</sub>/Au interface was assumed to preserve the topological surface state (TSS) of Sb<sub>2</sub>Te<sub>3</sub>, which mediates the SCC. Al is explored as an alternative to Au for its long spin diffusion length. Spin pumping experiments indicate the absence of SCC in the Sb<sub>2</sub>Te<sub>3</sub>/Al/Co heterostructure. Core level and valence band photoemission spectroscopies reveal that Al forms stable compounds with Te and Sb, thereby quenching the TSS of Sb<sub>2</sub>Te<sub>3</sub>, while the TSS is preserved upon the formation of the TI/Au interface. These results demonstrate directly the major influence of material chemistry and highlight the role of TSS on the SCC efficiency in TI-based devices.