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arXiv · 2105.13788

Role of symmetry mismatch, charge transfer and low dimensionality in the magnetic order of CaMnO$_3$/SrTiO$_3$ ultrathin heterostructures

M. A. Barral·A. M. Llois·S. Di Napoli
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Abstract

By means of ab initio calculations, we study the effect of charge transfer and symmetry mismatch on the magnetic and electronic properties of CaMnO$_3$ ultrathin films, epitaxially grown on SrTiO$_3$ (001). We find that the interplay of these degrees of freedom, together with the low dimensionality and the strain imposed by the substrate, changes the bulk occupancy of the Mn e_$g$ orbitals, which determines the magnetic configuration of the ultrathin CMO films. A transition from an insulating G-type to a metallic A-type antiferromagnetic configuration is stabilized.

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M. A. Barral, A. M. Llois, S. Di Napoli. 2021-05-28. Role of symmetry mismatch, charge transfer and low dimensionality in the magnetic order of CaMnO$_3$/SrTiO$_3$ ultrathin heterostructures. https://doi.org/10.1063/9.0000177

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