Spin Hall Effect in Bilayer Graphene Combined with an Insulator up to Room Temperature

• DOI: 10.1021/acs.nanolett.0c01428
• Publication Date: 2020-05-14T18:34:48Z
• Authors: C. K. Safeer; Josep Ingla-Aynés; Nerea Ontoso; Franz Herling; Wenjing Yan; Luis E. Hueso; Fèlix Casanova
• Keywords: Condensed Matter - Mesoscale and Nanoscale Physics; Mesoscale and Nanoscale Physics (cond-mat.mes-hall); FOS: Physical sciences; 02 engineering and technology; 0210 nano-technology; 7. Clean energy

12 pages, 4 figures, supporting information<br/>Spin-orbit coupling in graphene can be enhanced by chemical functionalization, adatom decoration or proximity with a van der Waals material. As it is expected that such enhancement gives rise to a sizeable spin Hall effect, a spin-to-charge current conversion phenomenon of technological relevance, it has sparked wide research interest. However, it has only been measured in graphene/transition metal dichalcogenide van der Waals heterostructures with limited scalability. Here, we experimentally demonstrate spin Hall effect up to room temperature in bilayer graphene combined with a nonmagnetic insulator, an evaporated bismuth oxide layer. The measured spin Hall effect raises most likely from an extrinsic mechanism. With a large spin-to-charge conversion efficiency, scalability, and ease of integration to electronic devices, we show a promising material heterostructure suitable for spin-based device applications.<br/>