| DOI | Trouver le DOI : https://doi.org/10.1103/PhysRevB.73.064107 |
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| Auteur | Rechercher : Stock, C.; Rechercher : Ellis, D.; Rechercher : Swainson, I. P.1; Rechercher : Xu, Guangyong; Rechercher : Hiraka, H.; Rechercher : Zhong, Z.; Rechercher : Luo, H.; Rechercher : Zhao, X.; Rechercher : Viehland, D.; Rechercher : Birgeneau, R. J.; Rechercher : Shirane, G. |
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| Affiliation | - Conseil national de recherches du Canada. Centre canadien de faisceaux de neutrons du CNRC
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| Format | Texte, Article |
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| Sujet | lead compounds; neutron diffraction; phonons; relaxor ferroelectrics; soft modes; solid-state phase transformations; X-ray diffraction |
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| Résumé | Using neutron elastic and inelastic scattering and high-energy x-ray diffraction, we present a comparison of 40% Pb(Mg₁/₃Nb₂/₃)O₃-60%PbTiO₃ (PMN-60PT) with pure Pb(Mg₁/₃Nb₂/₃)O₃ (PMN) and PbTiO₃ (PT). We measure the structural properties of PMN-60PT to be identical to pure PT, however, the lattice dynamics are exactly that previously found in relaxors PMN and Pb(Zn₁/₃Nb₂/₃)O₃ (PZN). PMN-60PT displays a well-defined macroscopic structural transition from a cubic to tetragonal unit cell at 550 K. The diffuse scattering is shown to be weak indicating that the structural distortion is long-range in PMN-60PT and short-range polar correlations (polar nanoregions) are not present. Even though polar nanoregions are absent, the soft optic mode is short-lived for wave vectors near the zone center. Therefore PMN-60PT displays the same waterfall effect as prototypical relaxors PMN and PZN. We conclude that it is random fields resulting from the intrinsic chemical disorder which is the reason for the broad transverse optic mode observed in PMN and PMN-60PT near the zone center and not due to the formation of short-ranged polar correlations. Through our comparison of PMN, PMN-60PT, and pure PT, we interpret the dynamic and static properties of the PMN₋ₓPT system in terms of a random field model in which the cubic anisotropy term dominates with increasing doping of PbTiO3. |
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| Date de publication | 2006-02-13 |
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| Maison d’édition | American Physical Society |
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| Dans | |
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| Langue | anglais |
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| Publications évaluées par des pairs | Oui |
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| Numéro NPARC | 12328815 |
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| Exporter la notice | Exporter en format RIS |
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| Signaler une correction | Signaler une correction (s'ouvre dans un nouvel onglet) |
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| Identificateur de l’enregistrement | b30edd1f-1d23-4d2f-a26e-10c88750593a |
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| Enregistrement créé | 2009-09-10 |
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| Enregistrement modifié | 2023-10-04 |
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