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arXiv · 1706.07382

Real-space study of the optical absorption in alternative phases of silicon

Chin Shen Ong·Sinisa Coh·Marvin L. Cohen·Steven G. Louie
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Abstract

We introduce a real-space approach to understand the relationship between optical absorption and crystal structure. We apply this approach to alternative phases of silicon, with a focus on the Si$_{20}$ crystal phase as a case study. We find that about 83% of the changes in the calculated low-energy absorption in Si$_{20}$ as compared to Si in the diamond structure can be attributed to reducing the differences between the on-site energies of the bonding and anti-bonding orbitals as well as increasing the hopping integrals for specific Si-Si bonds.

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Chin Shen Ong, Sinisa Coh, Marvin L. Cohen, Steven G. Louie. 2017-06-22. Real-space study of the optical absorption in alternative phases of silicon. https://doi.org/10.1103/physrevmaterials.1.075408

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