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arXiv · 1804.01509

Liquid-like Free Carrier Solvation and Band Edge Luminescence in Lead-Halide Perovskites

Yinsheng Guo·Omer Yaffe·Trevor D. Hull·Jonathan S. Owen·David R. Reichman·Louis E. Brus
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Abstract

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 an anharmonic LO phonon at about 20 meV (160 cm-1) in the lead-bromide framework. We reconcile the liquid-like picture with more standard solid-state theories of the Stokes shift in crystalline semiconductors.

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Yinsheng Guo, Omer Yaffe, Trevor D. Hull, Jonathan S. Owen, David R. Reichman, Louis E. Brus. 2018-04-04. Liquid-like Free Carrier Solvation and Band Edge Luminescence in Lead-Halide Perovskites. https://arxiv.org/abs/1804.01509

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