Making EuO multiferroic by epitaxial strain engineering

0537611 - FZÚ 2021 RIV GB eng J - Journal Article
Goian, Veronica - Held, R. - Bousquet, E. - Yuan, Y. - Melville, A. - Zhou, H. - Gopalan, V. - Ghosez, Ph. - Spaldin, N.A. - Schlom, D. G. - Kamba, Stanislav
Making EuO multiferroic by epitaxial strain engineering.
Communications Materials. Roč. 1, č. 1 (2020), s. 1-10, č. článku 74. E-ISSN 2662-4443
R&D Projects: GA MŠMT(CZ) EF16_019/0000760; GA ČR GA18-09265S
Grant - others:OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Institutional support: RVO:68378271
Keywords : strain * multiferroics * IR spectroscopy * DFT calculations * soft phonon
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Method of publishing: Open access

We provide clear experimental indications that ferroelectricity can be induced by epitaxial tensile strain in the ferromagnetic simple binary oxide EuO. We investigate the ferroelectric phase transition using infrared reflectance spectroscopy, finding that the frequency of the soft optical phonon reduces with increasing tensile strain and decreasing temperature. We observe such a soft mode anomaly at 100 K in (EuO)2/(BaO)2 superlattices grown epitaxially on (LaAlO3)0.29-(SrAl1/2Ta1/2O3)0.71 substrates, which is a typical signature for a displacive ferroelectric phase transition. The EuO in this superlattice is nominally subjected to 6.4% biaxial tensile strain. We interpret our results with new first-principles density functional calculations using a hybrid functional.

Permanent Link: http://hdl.handle.net/11104/0315426