%0 Journal Article %1 guo2019dynamic %A Guo, Yinsheng %A Yaffe, Omer %A Hull, Trevor D. %A Owen, Jonathan S. %A Reichman, David R. %A Brus, Louis E. %D 2019 %J Nature Communications %K dynamic emission shift stokes %N 1 %P 1175-- %R 10.1038/s41467-019-09057-5 %T Dynamic emission Stokes shift and liquid-like dielectric solvation of band edge carriers in lead-halide perovskites %U https://doi.org/10.1038/s41467-019-09057-5 %V 10 %X Lead-halide perovskites have emerged as promising materials for photovoltaic and optoelectronic applications. Their significantly anharmonic lattice motion, in contrast to conventional harmonic semiconductors, presents a conceptual challenge in understanding the genesis of their exceptional optoelectronic properties. Here we report a strongly temperature dependent luminescence Stokes shift in the electronic spectra of both hybrid and inorganic lead-bromide perovskite single crystals. This behavior stands in stark contrast to that exhibited by more conventional crystalline semiconductors. We correlate the electronic spectra with the anti-Stokes and Stokes Raman vibrational spectra. Dielectric solvation theories, originally developed for excited molecules dissolved in polar liquids, reproduce our experimental observations. Our approach, which invokes a classical Debye-like relaxation process, captures the dielectric response originating from the incipient anharmonicity of the LO phonon at about 20 meV (160 cm−1) in the lead-bromide framework. We reconcile this liquid-like model incorporating thermally-activated dielectric solvation with more standard solid-state theories of the emission Stokes shift in crystalline semiconductors.

@article{guo2019dynamic, abstract = {Lead-halide perovskites have emerged as promising materials for photovoltaic and optoelectronic applications. Their significantly anharmonic lattice motion, in contrast to conventional harmonic semiconductors, presents a conceptual challenge in understanding the genesis of their exceptional optoelectronic properties. Here we report a strongly temperature dependent luminescence Stokes shift in the electronic spectra of both hybrid and inorganic lead-bromide perovskite single crystals. This behavior stands in stark contrast to that exhibited by more conventional crystalline semiconductors. We correlate the electronic spectra with the anti-Stokes and Stokes Raman vibrational spectra. Dielectric solvation theories, originally developed for excited molecules dissolved in polar liquids, reproduce our experimental observations. Our approach, which invokes a classical Debye-like relaxation process, captures the dielectric response originating from the incipient anharmonicity of the LO phonon at about 20 meV (160 cm−1) in the lead-bromide framework. We reconcile this liquid-like model incorporating thermally-activated dielectric solvation with more standard solid-state theories of the emission Stokes shift in crystalline semiconductors.}, added-at = {2019-03-14T11:24:25.000+0100}, author = {Guo, Yinsheng and Yaffe, Omer and Hull, Trevor D. and Owen, Jonathan S. and Reichman, David R. and Brus, Louis E.}, biburl = {https://www.bibsonomy.org/bibtex/2156b28b88d271cb99577aba881a7a33f/sere}, doi = {10.1038/s41467-019-09057-5}, interhash = {175f0624be4cb23f9d96a7c9db477e04}, intrahash = {156b28b88d271cb99577aba881a7a33f}, issn = {20411723}, journal = {Nature Communications}, keywords = {dynamic emission shift stokes}, number = 1, pages = {1175--}, refid = {Guo2019}, timestamp = {2019-03-14T11:24:25.000+0100}, title = {Dynamic emission Stokes shift and liquid-like dielectric solvation of band edge carriers in lead-halide perovskites}, url = {https://doi.org/10.1038/s41467-019-09057-5}, volume = 10, year = 2019 }