Extended Huckel theory for bandstructure, chemistry and transport. I. Carbon Nanotubes

TL;DR

This paper introduces a semi-empirical Extended Huckel Theory method for calculating electronic properties of materials, demonstrated on carbon nanotubes, offering a practical balance between accuracy and computational efficiency.

Contribution

The paper develops and applies an extended Huckel theory approach for bandstructure, surface states, and transport in materials, specifically focusing on carbon nanotubes.

Findings

Huckel bandstructure provides a good approximation for quantum transport.

The method balances accuracy and computational cost effectively.

Application to CNTs shows promising results for electronic property calculations.

Abstract

We describe a semi-empirical atomic basis Extended H\"uckel Theoretical (EHT) technique that can be used to calculate bulk bandstructure, surface density of states, electronic transmission and interfacial chemistry of various materials within the same computational platform. We apply this method to study multiple technologically important systems, starting with carbon-nanotubes (CNT) and their interfaces in this paper, and silicon-based heterostructures in our follow-up paper. We find that when it comes to quantum transport through interesting, complex heterostructures, the Huckel bandstructure offers a fair and practical compromise between orthogonal tight-binding theories (OTB) with limited transferability between environments under large distortion, and density functional theories (DFT) that are computationally quite expensive for the same purpose.