The number of transmission channels through a single-molecule junction

TL;DR

This paper investigates the number of transmission channels in single-molecule junctions, revealing it equals the degeneracy of the molecular orbital near the Fermi level, using advanced many-body calculations.

Contribution

It introduces a realistic many-body approach to determine transmission channels, linking them to molecular orbital degeneracy in junctions.

Findings

Number of transmission channels equals the degeneracy of the closest molecular orbital.

Uses state-of-the-art many-body techniques for realistic modeling.

Includes effects of screening and van der Waals interactions.

Abstract

We calculate transmission eigenvalue distributions for Pt-benzene-Pt and Pt-butadiene-Pt junctions using realistic state-of-the-art many-body techniques. An effective field theory of interacting $\pi$-electrons is used to include screening and van der Waals interactions with the metal electrodes. We find that the number of dominant transmission channels in a molecular junction is equal to the degeneracy of the molecular orbital closest to the metal Fermi level.