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arXiv · 2401.04533

Simulation of ion demixing in halide perovskites using Cahn-Hilliard equation

V. Holý·M. Dopita·L. Horák·J. Holovský
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Abstract

Light-induced ion demixing in mixed-halide perovskites is simulated numerically using the phenomenological Cahn-Hilliard equation. In the model we consider the energy of local elastic deformation as well as the contribution of free carriers, assuming both the polaron and the bandgap-fluctuation models. The simulation shows that elastic deformation suppresses the demixing while free carriers promote it, however both effects lead to different ion distributions. The free-carrier-induced demixing appears only for larger starting random fluctuations of the ion concentration.

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V. Holý, M. Dopita, L. Horák, J. Holovský. 2024-01-09. Simulation of ion demixing in halide perovskites using Cahn-Hilliard equation. https://arxiv.org/abs/2401.04533

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