Gigahertz Frame Rate Imaging of Charge-Injection Dynamics in a Molecular Light Source

Abstract

Light sources on the scale of single molecules can be addressed and characterized on their proper subnanometer scale by scanning tunneling microscopy induced luminescence (STML). Such a source can be driven by defined short charge pulses while the luminescence is detected with sub-nanosecond resolution. We introduce an approach to concurrently image the molecular emitter, which is based on an individual defect, with its local environment along with its luminescence dynamics at a resolution of a billion frames per second. The observed dynamics can be assigned to the single electron capture occurring in the low-nanosecond regime. While the emitter's location on the surface remains fixed, the scanning of

Mapping Lamb, Stark, and Purcell Effects at a Chromophore-Picocavity Junction with Hyper-Resolved Fluorescence Microscopy

“…The low-ps excited-state lifetime constitutes a reference point in that respect. Both the tunneling current (the average time between consecutive charges) and injection from the substrate occur either on the order of or slower than 1 ns [67]. Therefore, a current-excited molecule will decay before another charge interacts with it, and thus the current can be neglected in the model.…”