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arXiv · 1812.04903

Ultrafast THz probe of photo-induced polarons in lead-halide perovskites

Eugenio Cinquanta·Daniele Meggiolaro·Silvia G. Motti·Marina Gandini·Marcelo J. P. Alcocer·Quinten Adriaan Akkerman·Caterina Vozzi·Liberato Manna·Filippo De Angelis·Annamaria Petrozza·Salvatore Stagira
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Abstract

We study the nature of photo-excited charge carriers in CsPbBr3 nanocrystal thin films by ultrafast optical pump - THz probe spectroscopy. We observe a deviation from a pure Drude dispersion of the THz dielectric response that is ascribed to the polaronic nature of carriers; a transient blueshift of observed phonon frequencies is indicative of the coupling between photogenerated charges and stretching-bending modes of the deformed inorganic sublattice, as confirmed by DFT calculations.

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Eugenio Cinquanta, Daniele Meggiolaro, Silvia G. Motti, Marina Gandini, Marcelo J. P. Alcocer, Quinten Adriaan Akkerman, Caterina Vozzi, Liberato Manna, Filippo De Angelis, Annamaria Petrozza, Salvatore Stagira. 2018-12-12. Ultrafast THz probe of photo-induced polarons in lead-halide perovskites. https://doi.org/10.1103/physrevlett.122.166601

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