2020/06/03 by Jing Wang, Miša Anđelković, Gaofeng Wang +2 · 5 citations
Materials Science · Mathematics · Physics and Astronomy · #Carbon Nanotubes in Composites #Chemical physics #Condensed matter physics #Geometry #Graphene #Graphene research and applications #Materials science #Mathematics #Nanotechnology #Physics #Quantum and electron transport phenomena #Symmetry (geometry) #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.102.064108
published in Physical review. B./Physical review. B 102(6) (American Physical Society) · 8 pages and 12 figures
arxiv created 2020/06/03 · openalex publication_date 2020/08/25 · arxiv updated 2020/09/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Atomic collapse can be observed in graphene because of its large ``effective'' fine structure constant, which enables this phenomenon to occur for an impurity charge as low as Zc\ensuremath∼1--2. Here we investigate the effect of the sublattice symmetry on molecular collapse in two spatially separated charge tunable vacancies, which are located on the same (A-A type) or different (A-B type) sublattices. We find that the broken sublattice symmetry: (1) does not affect the location of the main bonding and antibonding molecular collapse peaks, (2) but shifts the position of the satellite peaks, because they are a consequence of the breaking of the local sublattice symmetry, and (3) there are vacancy characteristic collapse peaks that only occur for A-B type vacancies, which can be employed to distinguish them experimentally from the A-A type. As the charge, energy, and separation distance increase, the additional collapse features merge with the main molecular collapse peaks. We show that the spatial distribution around the vacancy site of the collapse states allows us to differentiate the molecular from the frustrated collapse.