Abstract
The interconversion between singlet and triplet spin states of photogenerated radical pairs is a genuine quantum process, which can be harnessed to coherently manipulate the recombination products through a magnetic field. This control is central to such diverse fields as molecular optoelectronics, quantum sensing, quantum biology and spin chemistry, but its effect is typically fairly weak in pure molecular systems. Here we introduce hybrid radical pairs constructed from semiconductor quantum dots and organic molecules. The large g-factor difference enables us to directly observe the radical-pair spin quantum beats usually hidden in previous studies, which are further accelerated by the strong exchange coupling of radical pairs enabled by the quantum confinement of quantum dots. The rapid quantum beats enable the efficient and coherent control of charge recombination dynamics at room temperature, with the modulation level of the yield of spin-triplet products reaching 400%.
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Data availability
All data are available in the Article or its Supplementary Information, and are available from the corresponding author upon request. They are also available via figshare at https://doi.org/10.6084/m9.figshare.27262569. Source data are provided with this paper.
Code availability
The codes developed for this study are available from the corresponding author upon request.
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Acknowledgements
K.W. acknowledges financial support from the National Natural Science Foundation of China (grant no. 22173098), the Chinese Academy of Sciences (grant nos. XDB0970303 and YSBR-007), Dalian Institute of Chemical Physics (grant no. DICP I202106) and the Fundamental Research Funds for the Central Universities (grant no. 20720220009). K.W. also acknowledges the New Cornerstone Science Foundation through the XPLORER PRIZE. M.L. acknowledges Y. Lv and J. Du for the transmission electron microscopy measurements of QDs.
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K.W. initiated the idea and supervised the project. M.L. synthesized the samples and performed the spectroscopy with the help of J.Z. M.L. and J.Z. performed the simulations. G.Z., Y.L., Y.Y. and K.G. participated in the spectroscopy experiments. K.W. and M.L. wrote the manuscript with inputs from all authors.
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Liu, M., Zhu, J., Zhao, G. et al. Coherent manipulation of photochemical spin-triplet formation in quantum dot–molecule hybrids. Nat. Mater. 24, 260–267 (2025). https://doi.org/10.1038/s41563-024-02061-1
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DOI: https://doi.org/10.1038/s41563-024-02061-1
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