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arXiv · 1705.01846

Photoinduced Domain Pattern Transformation in Ferroelectric/Dielectric Superlattices

Youngjun Ahn·Joonkyu Park·Anastasios Pateras·Matthew B. Rich·Qingteng Zhang·Pice Chen·Mohammed H. Yusuf·Haidan Wen·Matthew Dawber·Paul G. Evans
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Abstract

The nanodomain pattern in ferroelectric/dielectric superlattices transforms to a uniform polarization state under above-bandgap optical excitation. X-ray scattering reveals a disappearance of domain diffuse scattering and an expansion of the lattice. The reappearance of the domain pattern occurs over a period of seconds at room temperature, suggesting a transformation mechanism in which charge carriers in long-lived trap states screen the depolarization field. A Landau-Ginzburg-Devonshire model predicts changes in lattice parameter and a critical carrier concentration for the transformation.

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Youngjun Ahn, Joonkyu Park, Anastasios Pateras, Matthew B. Rich, Qingteng Zhang, Pice Chen, Mohammed H. Yusuf, Haidan Wen, Matthew Dawber, Paul G. Evans. 2017-08-04. Photoinduced Domain Pattern Transformation in Ferroelectric/Dielectric Superlattices. https://doi.org/10.1103/physrevlett.119.057601

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