Fluorescence and phosphorescence from individual C$_{60}$ molecules excited by local electron tunneling

TL;DR

This study demonstrates that localized electron tunneling via STM can excite and identify fluorescence and phosphorescence in individual C60 molecules, enabling chemical recognition at the single-molecule level.

Contribution

It introduces a method to excite and analyze luminescence from single molecules using STM, revealing electronic and vibronic transitions for chemical identification.

Findings

Successful excitation of luminescence from single C60 molecules.

Identification of electronic and vibronic transitions.

Chemical recognition at the single-molecule scale.

Abstract

Using the highly localized current of electrons tunneling through a double barrier Scanning Tunneling Microscope (STM) junction, we excite luminescence from a selected C$_{60}$ molecule in the surface layer of fullerene nanocrystals grown on an ultrathin NaCl film on Au(111). In the observed luminescence fluorescence and phosphorescence spectra, pure electronic as well as vibronically induced transitions of an individual C$_{60}$ molecule are identified, leading to unambiguous chemical recognition on the single-molecular scale.