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arXiv · 1702.03378

Excitonic coupling dominates the homogeneous photoluminescence excitation linewidth in semicrystalline polymeric semiconductors

Pascal Grégoire·Eleonora Vella·Matthew Dyson·Claudia M. Bazán·Richard Leonelli·Natalie Stingelin·Paul N. Stavrinou·Eric R. Bittner·Carlos Silva
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Abstract

We measure the homogeneous excitation linewidth of regioregular poly(3-hexylthiophene), a model semicrystalline polymeric semiconductor, by means of two-dimensional coherent photoluminescence excitation spectroscopy. At a temperature of 8\,K, we find a linewidth that is always $\gtrsim 110$\,meV full-width-at-half-maximum, which is a significant fraction of the total linewidth. It displays a spectral dependence and is minimum near the 0--0 origin peak. We interpret this spectral dependence of the homogeneous excitation linewidth within the context of a weakly coupled aggregate model.

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Pascal Grégoire, Eleonora Vella, Matthew Dyson, Claudia M. Bazán, Richard Leonelli, Natalie Stingelin, Paul N. Stavrinou, Eric R. Bittner, Carlos Silva. 2017-02-11. Excitonic coupling dominates the homogeneous photoluminescence excitation linewidth in semicrystalline polymeric semiconductors. https://doi.org/10.1103/physrevb.95.180201

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