Reports

Photon Emission at Molecular Resolution Induced by a Scanning Tunneling Microscope

Science  26 Nov 1993:
Vol. 262, Issue 5138, pp. 1425-1427
DOI: 10.1126/science.262.5138.1425

Abstract

The tip-surface region of a scanning tunneling microscope (STM) emits light when the energy of the tunneling electrons is sufficient to excite luminescent processes. These processes provide access to dynamic aspects of the local electronic structure that are not directly amenable to conventional STM experiments. From monolayer films of carbon-60 fullerenes on gold(110) surfaces, intense emission is observed when the STM tip is placed above an individual molecule. The diameter of this emission spot associated with carbon-60 is approximately 4 angstroms. These results demonstrate the highest spatial resolution of light emission to date with a scanning probe technique.