Effect of one-dimensional superlattice potentials on the band gap of two-dimensional materials

Shota Ono

doi:10.1063/1.4984069

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arXiv · 1705.09498

Effect of one-dimensional superlattice potentials on the band gap of two-dimensional materials

Shota Ono

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Abstract

Using the tight-binding approach, we analyze the effect of a one-dimensional superlattice (1DSL) potential on the electronic structure of black phosphorene and transition metal dichalcogenides. We observe that the 1DSL potential results in a decrease of the energy band gap of the two-dimensional (2D) materials. An analytical model is presented to relate the decrease in the direct-band gap to the different orbital characters between the valence band top and conduction band bottom of the 2D materials. The direct-to-indirect gap transition, which occurs under a 1DSL potential with an unequal barrier width, is also discussed.

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Shota Ono. 2017-05-26. Effect of one-dimensional superlattice potentials on the band gap of two-dimensional materials. https://doi.org/10.1063/1.4984069

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