Simple and efficient way of speeding up transmission calculations with $k$-point sampling

Jesper Toft Falkenberg; Mads Brandbyge

doi:10.3762/bjnano.6.164

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arXiv · 1505.03267

Simple and efficient way of speeding up transmission calculations with $k$-point sampling

Jesper Toft Falkenberg·Mads Brandbyge

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Abstract

The transmissions as functions of energy are central for electron or phonon transport in the Landauer transport picture. We suggest a simple and computationally "cheap" post-processing scheme to interpolate transmission functions over $k$-points to get smooth well-converged average transmission functions. This is relevant for data obtained using typical "expensive" first principles calculations where the leads/electrodes are described by periodic boundary conditions. We show examples of transport in graphene structures where a speed-up of an order of magnitude is easily obtained.

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Jesper Toft Falkenberg, Mads Brandbyge. 2015-05-13. Simple and efficient way of speeding up transmission calculations with $k$-point sampling. https://doi.org/10.3762/bjnano.6.164

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