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arXiv · 1506.04403

Sculpting the band gap: a computational approach

Kiran Prasai·Parthapratim Biswas·D. A. Drabold
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Abstract

Materials with optimized band gap are needed in many specialized applications. In this work, we demonstrate that Hellmann-Feynman forces associated with the gap states can be used to find atomic coordinates with a desired electronic density of states. Using tight-binding models, we show that this approach can be used to arrive at electronically designed models of amorphous silicon and carbon. We provide a simple recipe to include a priori electronic information in the formation of computer models of materials, and prove that this information may have profound structural consequences. An additional example of a graphene nanoribbon is provided to demonstrate the applicability of this approach to engineer 2-dimensional materials. The models are validated with plane-wave density functional calculations.

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Kiran Prasai, Parthapratim Biswas, D. A. Drabold. 2015-06-14. Sculpting the band gap: a computational approach. https://arxiv.org/abs/1506.04403

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