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arXiv · 2310.01114

The Co$^{2+}$-Ir$^{5+}$ orbital hybridization in LaCaCoIrO$_6$ double perovskite

L. Bufaiçal·L. S. I. Veiga·J. R. L. Mardegan·T. Pohlmann·S. Francoual·S. S. Dhesi·M. B. Fontes·E. M. Bittar
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Abstract

Here, we report on the structural, electronic, and magnetic properties of a polycrystalline sample of the LaCaCoIrO$_6$ double-perovskite investigated by means of synchrotron x-ray powder diffraction, x-ray absorption spectroscopy, and x-ray magnetic circular dichroism at the Co and Ir $L_{2,3}$ edges, magnetometry, and electrical transport. Our results indicate a configuration of nearly Co$^{2+}$/Ir$^{5+}$ configuration for the transition-metal ions, with spin canting within the Co antiferromagnetic superstructure responsible for the ferromagnetic-like behavior observed below 100 K. The highly insulating character of LaCaCoIrO$_6$ and its positive magnetoresistance further suggest that this antiferromagnetic superexchange interaction occurs through an indirect hybridization between the Co $e_g$ orbitals

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L. Bufaiçal, L. S. I. Veiga, J. R. L. Mardegan, T. Pohlmann, S. Francoual, S. S. Dhesi, M. B. Fontes, E. M. Bittar. 2023-10-02. The Co$^{2+}$-Ir$^{5+}$ orbital hybridization in LaCaCoIrO$_6$ double perovskite. https://doi.org/10.1016/j.jmmm.2023.171276

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