Can the ferroelectric soft mode trigger an antiferromagnetic phase transition?

0570671 - FZÚ 2024 RIV GB eng J - Journal Article
Alves Maia, André Filipe - Kadlec, Christelle - Savinov, Maxim - Vilarinho, R. - Moreira, J.A. - Bovtun, Viktor - Kempa, Martin - Míšek, Martin - Kaštil, Jiří - Prokhorov, Andriy - Maňák, Jan - Belik, A.A. - Kamba, Stanislav
Can the ferroelectric soft mode trigger an antiferromagnetic phase transition?
Journal of the European Ceramic Society. Roč. 43, č. 6 (2023), s. 2479-2487. ISSN 0955-2219. E-ISSN 1873-619X
R&D Projects: GA ČR(CZ) GA21-06802S; GA MŠMT(CZ) EF16_019/0000760; GA MŠMT(CZ) LM2018096
Grant - others:OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Institutional support: RVO:68378271
Keywords : multiferroics * perovskites * soft-modes * ferroelectrics
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 5.7, year: 2022
Method of publishing: Open access with time embargo
https://doi.org/10.1016/j.jeurceramsoc.2022.12.067

Type-II multiferroics, where spin interactions induce a ferroelectric polarization, are interesting due to large magnetoelectric coupling. We report on a new type of multiferroicity in the quadruple-perovskite BiMn3Cr4O12, where an antiferromagnetic phase is induced by the structural change at the ferroelectric phase transition. The displacive nature of the ferroelectric phase transition at 125 K, with a crossover to an order-disorder mechanism, is evidenced by a polar soft phonon in the THz range and a central mode. Dielectric and pyroelectric studies show that the ferroelectric critical temperature corresponds to the previously reported Néel temperature of the Cr3+ spins. An increase in ferroelectric polarization is observed below 48 K, coinciding with the Néel temperature of the Mn3+ spins. This increase in polarization is attributed to an enhanced magnetoelectric coupling, as no change in the crystal symmetry below 48 K is detected from infrared and Raman spectra.
Permanent Link: https://hdl.handle.net/11104/0342004