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arXiv · 1403.0707

Disappearance of the Dirac cone in silicene due to the presence of an electric field

D. A. Rowlands·Yu-Zhong Zhang
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Abstract

Using the two-dimensional ionic Hubbard model as a simple basis for describing the electronic structure of silicene in the presence of an electric field induced by the substrate, we use the coherent-potential approximation to calculate the zero-temperature phase diagram and associated spectral function at half filling. We find that any degree of symmetry-breaking induced by the electric field causes the silicene structure to lose its Dirac fermion characteristics, thus providing a simple mechanism for the disappearance of the Dirac cone.

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D. A. Rowlands, Yu-Zhong Zhang. 2014-03-04. Disappearance of the Dirac cone in silicene due to the presence of an electric field. https://doi.org/10.1088/1674-1056/23/3/037101

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