Sub-micron scale spectroscopy and microscopy of individual mesoscopic systems at cryogenic temperatures

Abstract

We report on a design of a laser scanning solid immersion microscope based on gradient index optics that is suitable for low-temperature excitation spectroscopy on the single molecule level. Further, we present a hole-burning study of a system consisting of molecular J-aggregates and associated trap states. These two studies are pre-requisites for microscopic high-resolution excitation spectroscopy performed on individual fibers of J-aggregates of pseudoisocyanine in a polymer film. Preliminary results of the microscopic study are further compared with microscopic reflection spectroscopy measured on identical systems at room temperature.