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arXiv · 2001.08908

From latent ferroelectricity to hyperferroelectricity in alkali lead halide perovskites

Guido Roma·Arthur Marronnier·Jacky Even
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Abstract

Using first principles calculations we show that several alkali lead halides potentially present collective ferroelectric polarization. This should occur at least at the nanoscale; it could be detected macroscopically provided it is not concealed by lattice vibrations in the temperature range of stability of the cubic perovskite phase. For potassium lead halides and for alkali lead fluorides, remarkably, the ferroelectric behavior turns hyper-ferroelectric, suggesting a more robust ferroelectric polarization in spite of depolarization potentials induced by charge accumulation on surfaces or interfaces.

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Guido Roma, Arthur Marronnier, Jacky Even. 2020-01-24. From latent ferroelectricity to hyperferroelectricity in alkali lead halide perovskites. https://doi.org/10.1103/physrevmaterials.4.092402

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