Single-molecule device prototypes for protein-based nanoelectronics: Negative differential resistance and current rectification in oligopeptides

Abstract

Using ab initio and semiempirical techniques, we investigate electrical conduction through individual oligopeptide molecules thiol bonded between gold nanocontacts. Our theory explains 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.