Ab initio electron-defect interactions using Wannier functions
Abstract

Computing electron–defect (e–d) interactions from first principles has remained impractical due to computational cost. Here we develop an interpolation scheme based on maximally localized Wannier functions (WFs) to efficiently computee–d interaction matrix elements. The interpolated matrix elements can accurately reproduce those computed directly without interpolation and the approach can significantly speed up calculations ofe–d relaxation times and defect-limited charge transport. We show example calculations of neutral vacancy defects in silicon and copper, for which we compute thee–d relaxation times on fine uniform and random Brillouin zone grids (and for copper, directly on the Fermi surface), as well as the defect-limited resistivity at low temperature. Our interpolation approach opens doors for atomistic calculations of charge carrier dynamics in the presence of defects.

Authors:
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Award ID(s):
Publication Date:
NSF-PAR ID:
10154073
Journal Name:
npj Computational Materials
Volume:
6
Issue:
1
ISSN:
2057-3960
Publisher:
Nature Publishing Group
National Science Foundation
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