Room temperature polariton lasing in ladder-type oligo(p-phenylene)s with different π-conjugation lengths
Abstract
Polariton lasing is coherent emission that originates from macroscopic accumulation of polariton population in the ground state, and is a promising route towards efficient coherent light sources as population inversion is not necessary. Unlike most Wannier‐Mott excitons in inorganic semiconductors, Frenkel excitons created in organic semiconductors have high oscillator strength and high exciton binding energy which sustain stable exciton‐polaritons at room temperature. Here, room temperature polariton lasing from a novel class of ladder‐type oligo(p‐phenylene)s is demonstrated. The polariton lasers exhibit a nonlinear increase of their spectrally integrated emission, a reduction in spectral linewidth, blue shift of emission peaks, and long‐range spatial coherence when the pump fluence is increased above threshold. By tuning the π‐conjugation length of the molecular structure, the polariton lasing wavelength can be changed from 430 nm to 457 nm. Optically pumped thresholds of 12 µJ cm−2 and 17 µJ cm−2 are observed, which are amongst the lowest values reported for polariton lasing in organic semiconductors.
Citation
Wei , M , Fang , M , Rajendran , S K , Lai , W-Y , Turnbull , G A & Samuel , I D W 2021 , ' Room temperature polariton lasing in ladder-type oligo(p-phenylene)s with different π-conjugation lengths ' , Advanced Photonics Research , vol. 2 , no. 1 , 2000044 . https://doi.org/10.1002/adpr.202000044
Publication
Advanced Photonics Research
Status
Peer reviewed
ISSN
2699-9293Type
Journal article
Rights
Copyright © 2020 The Authors. 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
Funding: The authors are grateful to EPSRC for support through the Hybrid Polaritonics Program grant (EP/M025330/1). M. W. acknowledges the China Scholarship Council for providing Ph.D. funding. M. Fang and W.-Y. Lai acknowledge financial support from the National Natural Science Foundation of China (21835003, 21422402, 21674050), the Natural Science Foundation of Jiangsu Province (BE2019120) for the synthesis of the ladder-type oligo(p-phenylene) molecules, 2L-F and 4L-F.Collections
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