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arXiv · 1905.11113

Removing all periodic boundary conditions: Efficient non-equilibrium Green function calculations

Nick Papior·Gaetano Calogero·Susanne Leitherer·Mads Brandbyge
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Abstract

We describe a method and its implementation for calculating electronic structure and electron transport without approximating the structure using periodic super-cells. This effectively removes spurious periodic images and interference effects. Our method is based on already established methods readily available in the non-equilibrium Green function formalism and allows for non-equilibrium transport. We present examples of a N defect in graphene, finite voltage bias transport in a point-contact to graphene, and a graphene-nanoribbon junction. This method is less costly, in terms of CPU-hours, than the super-cell approximation.

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Nick Papior, Gaetano Calogero, Susanne Leitherer, Mads Brandbyge. 2019-05-27. Removing all periodic boundary conditions: Efficient non-equilibrium Green function calculations. https://doi.org/10.1103/physrevb.100.195417

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