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Updated: Oct 17, 2025
Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Second-order Raman spectra of a LiNbO3:Tb crystal
N V Sidorov1, M N Palatnikov1, V S Gorelik2
1Tananaev Institute of Chemistry - Subdivision of the Federal Research Centre «Kola Science Centre of the Russian Academy of Sciences», 184206 Apatity City, Russia.
Abstract:
Additional bands have been discovered for the first time in the Raman spectra of terbium doped lithium niobate crystals. The bands have been determined in the high-frequency region and have been attributed to the overtone states of the second order of polar fundamental modes of the crystal lattice. It has been established that Raman spectrum of terbium doped lithium niobate contains bands with frequencies exceeding the overtones of the highest-frequency fundamental polar modes of A1(Z) and E(X, Y) symmetry types. The observed features of the second-order Raman spectra have been interpreted as a manifestation of bound states of phonons - biphonons.
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