Tip-enhanced molecular fluorescence microscopy with atomic-scale resolution
Rev. Mod. Phys. 98, 025007 – Published 30 June, 2026
DOI: https://doi.org/10.1103/pqvw-kv92
Abstract
The confinement of the electromagnetic near field at the atomically sharp apex of a scanning tunneling microscope (STM) tip enables the investigation of light-matter interactions with atomic-scale resolution. This marks a paradigm shift in the exploration of optical properties, reaching down to the scale of individual molecules. The combination of the optical response with the electronic transport properties of molecules in these STM junctions enables the acquisition of fluorescence spectral information from the molecules, including their intensity, spectral shifts, and broadenings, with exquisite spatial precision. Here an overview of recent developments in STM-induced luminescence is provided, together with the main concepts underlying the light-emission process. The review discusses in detail the electrical excitation mechanism and the interactions of the probed molecules with electromagnetic fields localized at the tip apex, examines recent progress in the field, including optically driven processes, and provides perspectives for future directions in hyperresolution microscopy.
