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Updated: Aug 7, 2025
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Anomalous Optical Properties of KTN:Li Ferroelectric Supercrystals
Ludovica Falsi1, Salvatore Macis1, Yehonatan Gelkop2
1Dipartimento di Fisica, Università di Roma "La Sapienza", 00185 Rome, Italy.
Abstract:
We report a spectroscopic investigation of potassium-lithium-tantalate-niobate (KTN:Li) across its room-temperature ferroelectric phase transition, when the sample manifests a supercrystal phase. Reflection and transmission results indicate an unexpected temperature-dependent enhancement of average index of refraction from 450 nm to 1100 nm, with no appreciable accompanying increase in absorption. Second-harmonic generation and phase-contrast imaging indicate that the enhancement is correlated to ferroelectric domains and highly localized at the supercrystal lattice sites. Implementing a two-component effective medium model, the response of each lattice site is found to be compatible with giant broadband refraction.
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