Dresden 2017 – wissenschaftliches Programm
CPP 46.8: Vortrag
Mittwoch, 22. März 2017, 16:45–17:00, CHE 91
Superradiance from two dimensional brick-wall aggregates of dye molecules: the role of size and shape for the temperature dependence — •Alexander Eisfeld1, Christian Marquardt2, and Moritz Sokolowski2 — 1MPI-PKS — 2Uni Bonn
Aggregates of interacting molecules can exhibit electronically excited states which are coherently delocalized over many molecules. This can lead to a strong enhancement of the fluorescence decay rate which is referred to as superradiance (SR). To date, the temperature dependence of SR is described by a 1/T law. Using an epitaxial dye layer and a Frenkel-exciton based model we provide both experimental and theoretical evidence that significant deviations from the 1/T behaviour can occur for brickwall-type aggregates of finite size leading even to a maximum of the SR at finite temperature. This is due to the presence of low energy excitations of weak or zero transition strength.