Topological phase transition and electrically tunable diamagnetism in silicene
TLDR
In this article, the spin Chern number of a monolayer of silicon atoms forming a honeycomb lattice is analyzed and the origin of pseudospin meron in the momentum space is found.Abstract:
Silicene is a monolayer of silicon atoms forming a honeycomb lattice. The lattice is actually made of two sublattices with a tiny separation. Silicene is a topological insulator, which is characterized by a full insulating gap in the bulk and helical gapless edges. It undergoes a phase transition from a topological insulator to a band insulator by applying external electric field. Analyzing the spin Chern number based on the effective Dirac theory, we find the origin to be a pseudospin meron in the momentum space. The peudospin degree of freedom arises from the two-sublattice structure. Our analysis makes clear the mechanism how a phase transition occurs from a topological insulator to a band insulator under increasing electric field. We propose a method to determine the critical electric field with the aid of diamagnetism of silicene. Diamagnetism is tunable by the external electric field, and exhibits a singular behaviour at the critical electric field. Our result is important also from the viewpoint of cross correlation between electric field and magnetism. Furthermore, nano-electromechanic devices transforming electric force to mechanical force may be feasible. Our finding will be important for future electro-magnetic correlated devices.read more
Citations
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Topologically protected refraction of robust kink states in valley photonic crystals
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Topological Phases in Two-Dimensional Materials: A Brief Review
Yafei Ren,Zhenhua Qiao,Qian Niu +2 more
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Monolayer Topological Insulators: Silicene, Germanene, and Stanene
TL;DR: In this paper, the authors report the recent progress on the theoretical aspects of monolayer topological insulators including silicene, germanene and stanene, and analyze the topological properties of generic honeycomb systems together with the classification of topologically insulators.
References
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TL;DR: In this article, the Hall conductance of a two-dimensional electron gas has been studied in a uniform magnetic field and a periodic substrate potential, where the Kubo formula is written in a form that makes apparent the quantization when the Fermi energy lies in a gap.
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Silicene: Compelling Experimental Evidence for Graphenelike Two-Dimensional Silicon
Patrick Vogt,Patrick Vogt,Paola De Padova,Claudio Quaresima,José Avila,Emmanouil Frantzeskakis,Maria C. Asensio,Andrea Resta,B. Ealet,Guy Le Lay +9 more
TL;DR: Here it is provided compelling evidence, from both structural and electronic properties, for the synthesis of epitaxial silicene sheets on a silver substrate, through the combination of scanning tunneling microscopy and angular-resolved photoemission spectroscopy in conjunction with calculations based on density functional theory.
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Substrate-induced bandgap opening in epitaxial graphene
Shuyun Zhou,Gey-Hong Gweon,Gey-Hong Gweon,Alexei V. Fedorov,Phillip N. First,W. A. de Heer,D.-H. Lee,Francisco Guinea,A. H. Castro Neto,Alessandra Lanzara,Alessandra Lanzara +10 more
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