Single-Molecule Device Prototypes for Protein-Based Nanoelectronics: Negative Differential Resistance and Current Rectification in Oligopeptides

TL;DR

This paper models electrical conduction in oligopeptides, explaining experimental current-voltage behaviors and predicting negative differential resistance, advancing the development of protein-based nanoelectronic devices.

Contribution

It provides the first theoretical explanation of oligopeptides' electrical properties without adjustable parameters, revealing mechanisms of rectification and negative differential resistance.

Findings

Explains experimental current-voltage characteristics of oligopeptides.

Predicts negative differential resistance at moderate biases.

Identifies the mechanism behind current rectification.

Abstract

We investigate electrical conduction through individual oligopeptide molecules thiol-bonded between gold nanocontacts using ab initio and semi-empirical techniques. Our theory explains for the first time these molecules' experimentally observed current-voltage characteristics, including both the magnitude and rectification of the current, and uses no adjustable parameters. We identify the mechanism of the observed current rectification, and predict that it will result in negative differential resistance at moderate biases. Our findings open the way to the realization of protein-based nanoelectronic devices.