2014/05/06 by Bo Zhang, Chunfeng Zhang, Rui Wang +7 · 19 citations
Engineering · Physics and Astronomy · #Exciton #Fission #Nonlinear system #Organic Electronics and Photovoltaics #Perovskite Materials and Applications #Singlet fission #Singlet state #Spectroscopy and Quantum Chemical Studies #Tetracene #Ultrashort pulse #cond-mat.mtrl-sci #physics.optics
paper · pdf · doi:10.1021/jz501736y
published in The Journal of Physical Chemistry Letters 5(20), 3462-3467 (American Chemical Society) · 20 pages, 4 figures, together with Supplementary Information
arxiv created 2014/05/06 · openalex publication_date 2014/09/26 · arxiv updated 2014/10/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Singlet fission holds the potential to dramatically improve the efficiency of solar energy conversion by creating two triplet excitons from one photoexcited singlet exciton in organic semiconductors. It is generally assumed that the singlet-fission rate is linearly dependent on the exciton density. Here we experimentally show that the rate of singlet fission has a nonlinear dependence on the density of photoexcited singlet excitons in tetracene films with small crystalline grains. We disentangle the spectrotemporal features of singlet and triplet dynamics from ultrafast spectroscopic data with the algorithm of singular value decomposition. The correlation between their temporal dynamics indicates a superlinear dependence of fission rate on the density of singlet excitons, which may arise from excitonic interactions.