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arXiv · 1805.02172

Relationship between crystal structure and multiferroic orders in orthorhombic perovskite manganites

Natalya S. Fedorova·Yoav William Windsor·Christoph Findler·Mahesh Ramakrishnan·Amadé Bortis·Laurenz Rettig·Kenta Shimamoto·Elisabeth M. Bothschafter·Michael Porer·Vincent Esposito·Yi Hu·Aurora Alberca·Thomas Lippert·Christof W. Schneider·Urs Staub·Nicola A. Spaldin
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Abstract

We use resonant and non-resonant X-ray diffraction measurements in combination with first-principles electronic structure calculations and Monte Carlo simulations to study the relationship between crystal structure and multiferroic orders in the orthorhombic perovskite manganites, o-$R$MnO$_3$ ($R$ is a rare-earth cation or Y). In particular, we focus on how the internal lattice parameters (Mn-O bond lengths and Mn-O-Mn bond angles) evolve under chemical pressure and epitaxial strain, and the effect of these structural variations on the microscopic exchange interactions and long-range magnetic order. We show that chemical pressure and epitaxial strain are accommodated differently by the crystal lattice of o-$R$MnO$_3$, which is key for understanding the difference in magnetic properties between bulk samples and strained films. Finally, we discuss the effects of these differences in the magnetism on the electric polarization in o-$R$MnO$_3$.

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Natalya S. Fedorova, Yoav William Windsor, Christoph Findler, Mahesh Ramakrishnan, Amadé Bortis, Laurenz Rettig, Kenta Shimamoto, Elisabeth M. Bothschafter, Michael Porer, Vincent Esposito, Yi Hu, Aurora Alberca, Thomas Lippert, Christof W. Schneider, Urs Staub, Nicola A. Spaldin. 2018-06-08. Relationship between crystal structure and multiferroic orders in orthorhombic perovskite manganites. https://doi.org/10.1103/physrevmaterials.2.104414

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