Exciton spin Hall effect in arc-shaped strained WSe2
2024 (English)In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 109, no 20, article id L201409Article in journal (Refereed) Published
Abstract [en]
Generating a pure spin current using electrons, which have degrees of freedom beyond spin, such as electric charge and valley index, presents challenges. In response, we propose a mechanism based on intervalley exciton dynamics in arc-shaped strained transition metal dichalcogenides (TMDs) to achieve the exciton spin Hall effect in an electrically insulating regime, without the need for an external electric field. The interplay between strain gradients and strain-induced pseudomagnetic fields results in a net Lorentz force on long-lived intervalley excitons in WSe2, carrying nonzero spin angular momentum. This process generates an exciton-mediated pure spin Hall current, resulting in opposite-sign spin accumulations and local magnetization on the two sides of the single-layer arc-shaped TMD. We demonstrate that the magnetic field induced by spin accumulation, at approximately ∼mT, can be detected using techniques such as superconducting quantum interference magnetometry or spatially resolved magneto-optical Faraday and Kerr rotations.
Place, publisher, year, edition, pages
American Physical Society (APS) , 2024. Vol. 109, no 20, article id L201409
National Category
Condensed Matter Physics
Identifiers
URN: urn:nbn:se:kth:diva-347637DOI: 10.1103/PhysRevB.109.L201409ISI: 001238521800002Scopus ID: 2-s2.0-85194937103OAI: oai:DiVA.org:kth-347637DiVA, id: diva2:1869232
Note
QC 20250630
2024-06-122024-06-122025-06-30Bibliographically approved