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arXiv · 1311.6082

An Environment-dependent Semi-Empirical Tight Binding Model Suitable for Electron Transport in Bulk Metals, Metal Alloys, Metallic Interfaces and Metallic Nanostructures I - Model and Validation

Ganesh Hegde·Michael Povolotskyi·Tillmann Kubis·Timothy Boykin·Gerhard Klimeck
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Abstract

Semi-Empirical Tight Binding (TB) is known to be a scalable and accurate atomistic representation for electron transport for realistically extended nano-scaled semiconductor devices that might contain millions of atoms. In this paper an environment-aware and transferable TB model suitable for electronic structure and transport simulations in technologically relevant metals, metallic alloys, metal nanostructures and metallic interface systems is described. Part I of this paper describes the development and validation of the new TB model. The new model incorporates intra-atomic diagonal and off-diagonal elements for implicit self-consistency and greater transferability across bonding environments. The dependence of the on-site energies on strain has been obtained by appealing to the Moments Theorem that links closed electron paths in the system to energy moments of angular momentum resolved local density of states obtained ab-initio. The model matches self-consistent DFT electronic structure results for bulk FCC metals with and without strain, metallic alloys, metallic interfaces and metallic nanostructures with high accuracy and can be used in predictive electronic structure and transport problems in metallic systems at realistically extended length scales

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Ganesh Hegde, Michael Povolotskyi, Tillmann Kubis, Timothy Boykin, Gerhard Klimeck. 2013-11-24. An Environment-dependent Semi-Empirical Tight Binding Model Suitable for Electron Transport in Bulk Metals, Metal Alloys, Metallic Interfaces and Metallic Nanostructures I - Model and Validation. https://doi.org/10.1063/1.4868977

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