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arXiv · 2405.06243

Ultrafast Anisotropic Polarization Dynamics of Electronic Ferroelectrics LuFe2O4

H. Yu·Y. Fukada·G. Nishida·K. Takubo·T. Ishikawa·S. Koshihara·N. Ikeda·Y. Okimoto
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Abstract

Femtosecond time-resolved second harmonic generation (SHG) measurements were performed at room temperature on a single crystal of LuFe2O4, which has recently attracted attention as an electronic ferroelectric material in which polarization occurs due to the real-space arrangement of Fe2+ and Fe3+. We irradiated the crystal with 800 nm laser pulses, traced the subsequent SHG changes, and observed anisotropic polarization dynamics: immediately after photoexcitation, the in-plane (ab-plane) component of the SHG greatly reduced, while the inter-plane (c-axis) SHG increased. This means that a hidden photoexcited state, in which the in-plane charge ordering is broken but the polarization along c-axis direction enhanced, has been created by photoexcitation, indicating that the electronic ferroelectricity can be controlled on a femtosecond scale.

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H. Yu, Y. Fukada, G. Nishida, K. Takubo, T. Ishikawa, S. Koshihara, N. Ikeda, Y. Okimoto. 2024-05-10. Ultrafast Anisotropic Polarization Dynamics of Electronic Ferroelectrics LuFe2O4. https://arxiv.org/abs/2405.06243

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