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arXiv · 1910.07531

Electronic band gaps from Quantum Monte Carlo methods

Yubo Yang·Vitaly Gorelov·Carlo Pierleoni·David M. Ceperley·Markus Holzmann
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Abstract

We develop a method for calculating the fundamental electronic gap of semiconductors and insulators using grand canonical Quantum Monte Carlo simulations. We discuss the origin of the bias introduced by supercell calculations of finite size and show how to correct the leading and subleading finite size errors either based on observables accessible in the finite-sized simulations or from DFT calculations. Our procedure is applied to solid molecular hydrogen and compared to experiment for carbon and silicon crystals.

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Yubo Yang, Vitaly Gorelov, Carlo Pierleoni, David M. Ceperley, Markus Holzmann. 2019-10-16. Electronic band gaps from Quantum Monte Carlo methods. https://doi.org/10.1103/physrevb.101.085115

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