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arXiv · 1504.05005

Electronic Transitions in Strained SmNiO_3 Thin Films

S. Catalano·M. Gibert·V. Bisogni·O. Peil·F. He·R. Sutarto·M. Viret·P. Zubko·R. Scherwitzl·A. Georges·G. A. Sawatzky·T. Schmitt·J. -M. Triscone
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Abstract

Nickelates are known for their metal to insulator transition (MIT) and an unusual magnetic ordering, occurring at T=T_Néel. Here, we investigate thin films of SmNiO_3 subjected to different levels of epitaxial strain. We find that the original bulk behavior (T_Néel<T_MI) is strongly affected by applying compressive strain to the films. For small compressive strains, a regime where T_Néel=T_MI is achieved, the paramagnetic insulating phase characteristic of the bulk compound is suppressed and the MIT becomes 1st order. Further increasing the in-plane compression of the SmNiO_3 lattice leads to the stabilization of a single metallic paramagnetic phase.

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S. Catalano, M. Gibert, V. Bisogni, O. Peil, F. He, R. Sutarto, M. Viret, P. Zubko, R. Scherwitzl, A. Georges, G. A. Sawatzky, T. Schmitt, J. -M. Triscone. 2015-04-20. Electronic Transitions in Strained SmNiO_3 Thin Films. https://doi.org/10.1063/1.4902138%2010.1063%2F1.4902138%2010.1063%2F1.4902138

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