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Interference and k-point sampling in the supercell approach to phase-coherent transport

K. S. Thygesen·K. W. Jacobsen
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Abstract

We present a systematic study of interference and k-point sampling effects in the supercell approach to phase-coherent electron transport. We use a representative tight-binding model to show that interference between the repeated images is a small effect compared to the error introduced by using only the Gamma-point for a supercell containing (3,3) sites in the transverse plane. An insufficient k-point sampling can introduce strong but unphysical features in the transmission function which can be traced to the presence of van Hove singularities in the lead. We present a first-principles calculation of the transmission through a Pt contact which shows that the k-point sampling is also important for realistic systems.

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K. S. Thygesen, K. W. Jacobsen. 2005-06-20. Interference and k-point sampling in the supercell approach to phase-coherent transport. https://doi.org/10.1103/physrevb.72.033401

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