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arXiv:1404.5118 · Physical Review B

Efficient basis expansion for describing linear and nonlinear electron dynamics in crystalline solids

Shunsuke A. Sato, Kazuhiro Yabana

Published Jun 30, 2014• 16 citations
arXivHTMLPDF

Abstract

We propose an efficient basis expansion for electron orbitals to describe real-time electron dynamics in crystalline solids. Although a conventional grid representation in the three-dimensional Cartesian coordinates works robustly, it requires a large amount of computational resources. To reduce computational costs, we consider basis expansion methods employing eigenstates of the ground state Hamiltonian with a truncation. We have found that adding occupied eigenstates of nearby $k$ points to the truncated basis functions composed of eigenstates of the original $k$ point is crucially important. We demonstrate the usefulness of the method for linear and nonlinear electron dynamics calculations in crystalline ${\mathrm{SiO}}_{2}$.

DOI
10.1103/physrevb.89.224305

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