Direct visualization of ultrafast lattice ordering triggered by an electron-hole plasma in 2D perovskites

Hao Zhang; Wenbin Li; Joseph Essman; Claudio Quarti; Isaac Metcalf; Wei-Yi Chiang; Siraj Sidhik; Jin Hou; Austin Fehr; Andrew Attar; Ming-Fu Lin; Alexander Britz; Xiaozhe Shen; Stephan Link; Xijie Wang; Uwe Bergmann; Mercouri G. Kanatzidis; Claudine Katan; Jacky Even; Jean-Christophe Blancon; Aditya D. Mohite

arXiv · 2204.01145

Direct visualization of ultrafast lattice ordering triggered by an electron-hole plasma in 2D perovskites

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Abstract

Direct visualization of ultrafast coupling between charge carriers and lattice degrees of freedom in photo-excited semiconductors has remained a long-standing challenge and is critical for understanding the light-induced physical behavior of materials under extreme non-equilibrium conditions. Here, by monitoring the evolution of the wave-vector resolved ultrafast electron diffraction intensity following above-bandgap photo-excitation, we obtain a direct visual of the structural dynamics in monocrystalline 2D perovskites. Analysis reveals a surprising, light-induced ultrafast lattice ordering resulting from a strong interaction between hot-carriers and the perovskite lattice, which induces an in-plane octahedra rotation, towards a more symmetric phase. Correlated ultrafast spectroscopy performed at the same carrier density as ultrafast electron diffraction reveals that the creation of a hot and dense electron-hole plasma triggers lattice ordering at short timescales by modulating the crystal cohesive energy. Finally, we show that the interaction between the carrier gas and the lattice can be altered by tailoring the rigidity of the 2D perovskite by choosing the appropriate organic spacer layer.

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Hao Zhang, Wenbin Li, Joseph Essman, Claudio Quarti, Isaac Metcalf, Wei-Yi Chiang, Siraj Sidhik, Jin Hou, Austin Fehr, Andrew Attar, Ming-Fu Lin, Alexander Britz, Xiaozhe Shen, Stephan Link, Xijie Wang, Uwe Bergmann, Mercouri G. Kanatzidis, Claudine Katan, Jacky Even, Jean-Christophe Blancon, Aditya D. Mohite. 2022-04-03. Direct visualization of ultrafast lattice ordering triggered by an electron-hole plasma in 2D perovskites. https://arxiv.org/abs/2204.01145

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