2019/01/31 by B. Feng, Baojie Feng, H. Zhou +18 · 33 citations
Materials Science · Physics and Astronomy · #Angle-resolved photoemission spectroscopy #Brillouin zone #Condensed matter physics #Dirac (video compression format) #Electronic structure #Graphene #Graphene research and applications #Materials science #Metamaterials and Metasurfaces Applications #Monolayer #Nanotechnology #Overlayer #Photoemission spectroscopy #Physics #Quantum mechanics #Silicene #Spectral line #Substrate (aquarium) #Superstructure #Topological Materials and Phenomena #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevlett.122.196801
published in Physical Review Letters 122(19), 196801 (American Physical Society) · 6 pages, 3 figures
arxiv created 2019/01/31 · openalex publication_date 2019/05/14 · arxiv updated 2019/05/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Atomic scale engineering of two-dimensional materials could create devices with rich physical and chemical properties. External periodic potentials can enable the manipulation of the electronic band structures of materials. A prototypical system is (3×3)-silicene/Ag(111), which has substrate-induced periodic modulations. Recent angle-resolved photoemission spectroscopy measurements revealed six Dirac cone pairs at the Brillouin zone boundary of Ag(111), but their origin remains unclear [Proc. Natl. Acad. Sci. USA 113, 14656 (2016)]. We used linear dichroism angle-resolved photoemission spectroscopy, the tight-binding model, and first-principles calculations to reveal that these Dirac cones mainly derive from the original cones at the K (K') points of free-standing silicene. The Dirac cones of free-standing silicene are split by external periodic potentials that originate from the substrate-overlayer interaction. Our results not only confirm the origin of the Dirac cones in the (3×3)-silicene/Ag(111) system, but also provide a powerful route to manipulate the electronic structures of two-dimensional materials.