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

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.

SUBMITTER: Falkenberg JT

PROVIDER: S-EPMC4578408 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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

Falkenberg Jesper Toft JT Brandbyge Mads M

Beilstein journal of nanotechnology 20150724

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 ...[more]

PMID: 26425412

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