Edge and Point‐Defect Induced Electronic and Magnetic Properties in Monolayer PtSe<sub>2</sub>
Jing‐Feng Li, Thomas Joseph, Mahdi Ghorbani‐Asl, Sadhu Kolekar, Arkady V. Krasheninnikov, Matthias Batzill
Abstract
Abstract Edges and point defects in layered dichalcogenides are important for tuning their electronic and magnetic properties. By combining scanning tunneling microscopy (STM) with density functional theory (DFT), the electronic structure of edges and point defects in 2D‐PtSe 2 are investigated where the 1.8 eV bandgap of monolayer PtSe 2 facilitates the detailed characterization of defect‐induced gap states by STM. The stoichiometric zigzag edge terminations are found to be energetically favored. STM and DFT show that these edges exhibit metallic 1D states with spin polarized bands. Various native point defects in PtSe 2 are also characterized by STM. A comparison of the experiment with simulated images enables identification of Se‐vacancies, Pt‐vacancies, and Se‐antisites as the dominant defects in PtSe 2 . In contrast to Se‐ or Pt‐vacancies, the Se‐antisites are almost devoid of gap states. Pt‐vacancies exhibit defect induced states that are spin polarized, emphasizing their importance for inducing magnetism in PtSe 2 . The atomic‐scale insights into defect‐induced electronic states in monolayer PtSe 2 provide the fundamental underpinning for defect engineering of PtSe 2 ‐monolayers and the newly identified spin‐polarized edge states offer prospects for engineering magnetic properties in PtSe 2 nanoribbons.