SINGLE-MOLECULE SPECTROSCOPY - SPONTANEOUS AND LIGHT-INDUCED FREQUENCY JUMPS

This paper reports on frequency jumps of single molecule excitation li nes: The first part deals with spontaneous spectral jumps (spectral di ffusion) and gives examples of what can be learned from investigations of spectral diffusion about the low temperature physics of amorphous solids. The second part of this article discusses light-induced freque ncy jumps in the crystalline system terrylene in p-terphenyl where rev ersible single molecule hole-burning allows the optical manipulation o f single absorbers in a remarkably controlled and reproducible fashion . Furthermore we demonstrate how this system permits investigations of one and the same chromophore over a period of a few weeks at least.