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Intriguing spin-lattice interactions in EuTiO₃.

ABSTRACT: During the last decade the cubic perovskite oxide EuTiO₃ (ETO) has attracted enormous novel research activities due to possible multiferroicity, hidden magnetism far above its Néel temperature at T_N = 5.5 K, structural instability at T_S = 282 K, possible application as magneto-electric optic device, and strong spin-lattice coupling. Here we address a novel highlight of this compound by showing that well below T_S a further structural phase transition occurs below 210 K without the application of an external magnetic field, and by questioning the assumed tetragonal symmetry of the structure below T_S where tiny deviations from true tetragonality are observed by birefringence and XRD measurements. It is suggested that the competition in the second nearest neighbor spin-spin interaction modulated by the lattice dynamics is at the origin of these new observations.

SUBMITTER: Bussmann-Holder A

PROVIDER: S-EPMC8460724 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Intriguing spin-lattice interactions in EuTiO3.

Bussmann-Holder Annette A Liarokapis Efthymios E Roleder Krystian K

Scientific reports 20210923 1

During the last decade the cubic perovskite oxide EuTiO3 (ETO) has attracted enormous novel research activities due to possible multiferroicity, hidden magnetism far above its Néel temperature at TN = 5.5 K, structural instability at TS = 282 K, possible application as magneto-electric optic device, and strong spin-lattice coupling. Here we address a novel highlight of this compound by showing that well below TS a further structural phase transition oc ...[more]

PMID: 34556751

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