IETS and quantum interference: propensity rules in the presence of an interference feature

TL;DR

This paper explores how quantum interference affects electron transmission in single molecules, showing how inelastic electron tunneling spectroscopy can identify interference features through vibrational mode suppression.

Contribution

It extends the understanding of propensity rules in inelastic electron tunneling spectroscopy to molecules exhibiting destructive quantum interference.

Findings

Quantum interference causes characteristic line shapes in current-voltage curves.

Inelastic electron tunneling spectroscopy can detect interference features via vibrational mode suppression.

The study clarifies how interference influences electron transmission and spectroscopic signatures.

Abstract

Destructive quantum interference in single molecule electronics is an intriguing phe- nomenon; however, distinguishing quantum interference effects from generically low transmission is not trivial. In this paper, we discuss how quantum interference ef- fects in the transmission lead to either low current or a particular line shape in current-voltage curves, depending on the position of the interference feature. Sec- ondly, we consider how inelastic electron tunneling spectroscopy can be used to probe the presence of an interference feature by identifying vibrational modes that are se- lectively suppressed when quantum interference effects dominate. That is, we expand the understanding of propensity rules in inelastic electron tunneling spectroscopy to molecules with destructive quantum interference.