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arXiv · 1803.09299

Four-spin ring interaction as a source of unconventional magnetic orders in orthorhombic perovskite manganites

Natalya S. Fedorova·Amadé Bortis·Christoph Findler·Nicola A. Spaldin
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Abstract

We use ab initio electronic structure calculations in combination with Monte Carlo simulations to investigate the magnetic and ferroelectric properties of bulk orthorhombic HoMnO$_3$ and ErMnO$_3$. Our goals are to explain the inconsistencies in the measured magnetic properties of the orthorhombic perovskite manganites (o-$R$MnO$_3$) with small rare-earth ($R$) cations or Y, as well as the contradictions between the directions and amplitudes of the electric polarizations reported by different experimental groups. Our computations stabilize several exotic magnetic orders (so-called w-spiral, H-AFM and I-AFM), whose presence resolve the contradictions in the measured magnetic and ferroelectric properties of o-$R$MnO$_3$. We show that these orders emerge due to strong four-spin ring exchange interactions.

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Natalya S. Fedorova, Amadé Bortis, Christoph Findler, Nicola A. Spaldin. 2018-04-12. Four-spin ring interaction as a source of unconventional magnetic orders in orthorhombic perovskite manganites. https://doi.org/10.1103/physrevb.98.235113

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