Proof of the elusive high-temperature incommensurate phase in CuO by spherical neutron polarimetry.
| Autor: | Qureshi N; Institut Laue-Langevin, 71 Avenue des Martyrs, 38042 Grenoble Cedex 9, France., Ressouche E; Université Grenoble Alpes, CEA, IRIG, MEM, MDN, F-38000 Grenoble, France., Mukhin A; Prokhorov General Physics Institute, Russian Academy of Sciences, ul. Vavilova 38, Moscow 119 991, Russia., Gospodinov M; Institute of Solid State Physics, Bulgarian Academy of Sciences, 1784 Sofia, Bulgaria., Skumryev V; Departament de Física, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.; Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona, Spain. |
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| Jazyk: | angličtina |
| Zdroj: | Science advances [Sci Adv] 2020 Feb 14; Vol. 6 (7), pp. eaay7661. Date of Electronic Publication: 2020 Feb 14 (Print Publication: 2020). |
| DOI: | 10.1126/sciadv.aay7661 |
| Abstrakt: | CuO is the only known binary multiferroic compound, and due to its high transition temperature into the multiferroic state, it has been extensively studied. In comparison to other prototype multiferroics, the nature and even the existence of the high-temperature incommensurate paraelectric phase (AF3) were strongly debated-both experimentally and theoretically-since it is stable for only a few tenths of a kelvin just below the Néel temperature. Until now, there is no proof by neutron diffraction techniques owing to its very small ordered Cu magnetic moment. Here, we demonstrate the potential of spherical neutron polarimetry, first, in detecting magnetic structure changes, which are not or weakly manifest in the peak intensity and, second, in deducing the spin arrangement of the so far hypothetic AF3 phase. Our findings suggest two coexisting spin density waves emerging from an accidental degeneracy of the respective states implying a delicate energy balance in the spin Hamiltonian. (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).) |
| Databáze: | MEDLINE |
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