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arXiv · 2105.01383

Density-functional approach to the band gaps of finite and periodic two-dimensional systems

Alberto Guandalini·Alice Ruini·Esa Räsänen·Carlo Andrea Rozzi·Stefano Pittalis
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Abstract

We present an approach based on density-functional theory for the calculation of fundamental gaps of both finite and periodic two-dimensional (2D) electronic systems. The computational cost of our approach is comparable to that of total energy calculations performed via standard semi-local forms. We achieve this by replacing the 2D local density approximation with a more sophisticated -- yet computationally simple -- orbital-dependent modeling of the exchange potential within the procedure by Guandalini et al. [Phys. Rev. B 99, 125140 (2019)]. We showcase promising results for semiconductor 2D quantum dots and artificial graphene systems, where the band structure can be tuned through, e.g., Kekul\'e distortion.

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Alberto Guandalini, Alice Ruini, Esa Räsänen, Carlo Andrea Rozzi, Stefano Pittalis. 2021-05-04. Density-functional approach to the band gaps of finite and periodic two-dimensional systems. https://doi.org/10.1103/physrevb.104.085110

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