| Proximity-Induced Spin-Valley Polarization in Silicene or Germanene on F-Doped WS2 Udo Schwingenschlogl1; Shahid Sattar1; Nirpendra Singh1; 1KING ABDULLAH UNIVERSITY OF SCIENCE AND TECHNOLOGY (KAUST), Thuwal, Saudi Arabia; PAPER: 23/Energy/Regular (Oral) SCHEDULED: 14:00/Thu. 24 Oct. 2019/Coralino ABSTRACT: Silicene and germanene are key materials for the field of valleytronics. Interaction with the substrate, however, which is necessary to support the electronically active medium, becomes a major obstacle. In the present work, we propose a substrate (F-doped WS<sub>2</sub>) that avoids detrimental effects and, at the same time, induces the required valley polarization, so that no further steps are needed for this purpose. The behavior is explained by proximity effects on silicene or germanene, as demonstrated by first-principle calculations. Broken inversion symmetry due to the presence of WS<sub>2</sub> opens a substantial band gap in silicene or germanene. F doping of WS<sub>2</sub> results in spin polarization which, in conjunction with proximity-enhanced spin-orbit coupling, creates sizable spin-valley polarizations. References: Physical Review B 94, 205415 (2016) |
