Fano Resonance in Single-Molecule Junctions

The Fano resonance in single-molecule junctions could be created by interaction with discrete and continuous molecular orbitals and enables effective electron transport modulation between constructive and destructive interference within a small energy range. However, direct observation of Fano resonance remains unexplored because of the disappearance of discrete orbitals by molecule-electrode coupling. We demonstrated the room-temperature observation of Fano resonance from electrochemical gated single-molecule conductance and current-voltage measurements of a para-carbazole anion junction. Theoretical calculations reveal that the negative charge on the nitrogen atom induces a localized HOMO on the molecular center, creating Fano resonance by interfering with the delocalized LUMO on the molecular backbone. Our findings demonstrate that the Fano resonance in electron transport through single-molecule junctions opens pathways for designs of interference-based electronic devices.

Automated summary

Fano resonance in single-molecule junctions is created by interaction between discrete and continuous molecular orbitals, allowing effective modulation of electron transport through interference. Direct observation of Fano resonance has been challenging due to the disappearance of discrete orbitals. Experimental demonstration of Fano resonance in electrochemical gated single-molecule conductance provides insights for designing interference-based electronic devices.