Single molecule spectroscopy: measurements of spectral shifts and fluorescence images

Abstract

Spectral shifts of the molecular resonance frequency have been observed since the early days of single molecule spectroscopy (SMS) [4]. We call these effects for concreteness light-induced spectral shifts (LISS) or spontaneous spectral shifts (SSS or S3) to distinguish the two possible reasons for the spectral change. In order to gain a more complete picture of these effects we have undertaken three different approaches.