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RESEARCH PRODUCT

Static and dynamic properties of low-temperature order in the one-dimensional semiconductor(NbSe4)3I

Jose Emilio LorenzoKatica BiljakovićDamir DominkoDamir StarešinićHrvoje SkenderovićDavor RistićJure DemsarMile IvandaSilvije Vdović

subject

DiffractionMaterials scienceCondensed matter physicsOrder (ring theory)02 engineering and technologyDielectric021001 nanoscience & nanotechnology01 natural sciencesFerroelectricitysymbols.namesakePhase (matter)0103 physical sciencessymbolsAntiferroelectricity010306 general physics0210 nano-technologySpectroscopyRaman spectroscopy

description

We investigated static and dynamic lattice properties in a quasi-one-dimensional charge-ordered semiconductor ${({\mathrm{NbSe}}_{4})}_{3}\mathrm{I}$ by using Raman, femtosecond pump-probe spectroscopy and x-ray diffraction. In addition to a well-documented pseudo-Jahn-Teller ferrodistortive structural transition at ${T}_{C}=274$ K, where the displacements of Nb ions lead to ferroelectric (FE) in-chain polarization with opposite direction in adjacent chains, all methods suggest an additional lowering of symmetry at ${T}^{*}\ensuremath{\approx}160$ K. Although antiferroelectric (AFE) phase is partially formed at ${T}_{C}$, our results consistently point to an enhancement of the interchain order at ${T}^{*}$, thus leading to AFE order-disorder transition, as supported by the earlier dielectric and structural studies.

https://doi.org/10.1103/physrevb.94.104113