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arXiv · 1302.2821

Electron Delocalization in Gate-Tunable Gapless Silicene

Yan-Yang Zhang·Wei-Feng Tsai·Kai Chang·X. -T. An·G. -P. Zhang·X. -C. Xie·Shu-Shen Li
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Abstract

The application of a perpendicular electric field can drive silicene into a gapless state, characterized by two nearly fully spin-polarized Dirac cones owing to both relatively large spin-orbital interactions and inversion symmetry breaking. Here we argue that since inter-valley scattering from non-magnetic impurities is highly suppressed by time reversal symmetry, the physics should be effectively single-Dirac-cone like. Through numerical calculations, we demonstrate that there is no significant backscattering from a single impurity that is non-magnetic and unit-cell uniform, indicating a stable delocalized state. This conjecture is then further confirmed from a scaling of conductance for disordered systems using the same type of impurities.

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Yan-Yang Zhang, Wei-Feng Tsai, Kai Chang, X. -T. An, G. -P. Zhang, X. -C. Xie, Shu-Shen Li. 2013-09-27. Electron Delocalization in Gate-Tunable Gapless Silicene. https://doi.org/10.1103/physrevb.88.125431

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