Low-threshold room temperature polariton lasing from fluorene-based oligomers
Abstract
Organic semiconductors possessing tightly bound Frenkel excitons are known to be attractive candidates for demonstrating polariton lasing at room temperature. As polariton lasing can occur without inversion, it is a potential route to very low threshold coherent light sources. However, so far, the thresholds of organic polariton lasers have generally been much higher than those of organic photon lasers. Here this problem has been addressed by investigating two new organic molecules with a structure combining fluorene and carbazole groups. The materials are readily deposited from solution and exhibit high photoluminescence quantum yields, high absorption coefficients, and large radiative decay rates in neat films. Room temperature polariton lasing is realized in both materials with incident thresholds of 13.5 and 9.7 µJ cm−2, corresponding to absorbed thresholds of 3.3 and 2.2 µJ cm−2, respectively. These are the lowest values reported to date for polariton lasing in organic semiconductor materials, and approach typical values for organic photon lasers. The step-like power dependent blue-shift of polariton modes indicates an interplay between different depletion channels of the exciton reservoir. This work brings practical room temperature polaritonic devices and future realization of electrically driven polariton lasers a step closer.
Citation
Wei , M , Ruseckas , A , Mai , V T N , Shukla , A , Allison , I , Lo , S-C , Namdas , E B , Turnbull , G & Samuel , I D W 2021 , ' Low-threshold room temperature polariton lasing from fluorene-based oligomers ' , Laser & Photonics Reviews , vol. 15 , no. 8 , 2100028 . https://doi.org/10.1002/lpor.202100028
Publication
Laser & Photonics Reviews
Status
Peer reviewed
ISSN
1863-8880Type
Journal article
Rights
Copyright © 2021 The Authors. Laser & Photonics Reviews published by Wiley-VCH GmbH. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Description
The authors are grateful to the Australian Research Council (ARC DP160100700 and DP200103036), Australian Department of Industry, Innovation and Science (AISRF53765), the UK Engineering and Physical Sciences Research Council (Grants EP/M025330/1 and EP/L017008/1), China Scholarship Council and the Rank Prize Funds for financial support.Collections
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