Silicene nanomeshes: bandgap opening by bond symmetry breaking and uniaxial strain
| Autor: | Gang Chen, Xinyu Fan, Meng-Meng Zheng, Tian-Tian Jia |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: |
Multidisciplinary
Materials science Condensed matter physics Band gap Silicene Point reflection Fermi level 02 engineering and technology 021001 nanoscience & nanotechnology 01 natural sciences Semimetal Article chemistry.chemical_compound symbols.namesake Condensed Matter::Materials Science Nanomesh chemistry Spin wave 0103 physical sciences symbols Symmetry breaking 010306 general physics 0210 nano-technology |
| Zdroj: | Scientific Reports |
| ISSN: | 2045-2322 |
| Popis: | Based on the first-principles calculations, we have investigated in detail the bandgap opening of silicene nanomeshes. Different to the mechanism of bandgap opening induced by the sublattice equivalence breaking, the method of degenerate perturbation through breaking the bond symmetry could split the π-like bands in the inversion symmetry preserved silicene nanomeshes, resulting into the πa1 − πa2 and πz1 − πz2 band sets with sizable energy intervals. Besides the bandgap opening in the nanomeshes with Dirac point being folded to Γ point, the split energy intervals are however apart away from Fermi level to leave the semimetal nature unchanged for the other nanomeshes with Dirac points located at opposite sides of Γ point as opposite pseudo spin wave valleys. A mass bandgap could be then opened at the aid of uniaxial strain to transfer the nanomesh to be semiconducting, whose width could be continuously enlarged until reaching its maximum Emax. Moreover, the Emax could also be tuned by controlling the defect density in silicene nanomeshes. These studies could contribute to the understanding of the bandgap engineering of silicene-based nanomaterials to call for further investigations on both theory and experiment. |
| Databáze: | OpenAIRE |
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