Microcavity-like exciton-polaritons can be the primary photoexcitation in bare organic semiconductors
Published version
Peer-reviewed
Repository URI
Repository DOI
Type
Change log
Authors
Abstract
Abstract: Strong-coupling between excitons and confined photonic modes can lead to the formation of new quasi-particles termed exciton-polaritons which can display a range of interesting properties such as super-fluidity, ultrafast transport and Bose-Einstein condensation. Strong-coupling typically occurs when an excitonic material is confided in a dielectric or plasmonic microcavity. Here, we show polaritons can form at room temperature in a range of chemically diverse, organic semiconductor thin films, despite the absence of an external cavity. We find evidence of strong light-matter coupling via angle-dependent peak splittings in the reflectivity spectra of the materials and emission from collective polariton states. We additionally show exciton-polaritons are the primary photoexcitation in these organic materials by directly imaging their ultrafast (5 × 106 m s−1), ultralong (~270 nm) transport. These results open-up new fundamental physics and could enable a new generation of organic optoelectronic and light harvesting devices based on cavity-free exciton-polaritons
Description
Keywords
Journal Title
Conference Name
Journal ISSN
Volume Title
Publisher
Publisher DOI
Sponsorship
EC | Horizon 2020 Framework Programme (EU Framework Programme for Research and Innovation H2020) (639088)
Vetenskapsrådet (Swedish Research Council) (2014-06948)
RCUK | Engineering and Physical Sciences Research Council (EPSRC) (EM20527, EP/M025330/1)