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arXiv · 1802.02815

Exotic Magnetism and Spin-Orbit Assisted Mott Insulating State in a $3d-5d$ Double Perovskite

A. S. Cavichini·M. T. Orlando·J. B. Depianti·J. L. Passamai Jr.·F. Damay·F. Porcher·E. Granado
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Abstract

The magnetic structure of Ca$_2$MnReO$_6$ double perovskite is investigated by neutron powder diffraction and bulk magnetization, showing dominant non-collinear Mn magnetic moments [$4.35(7)$ $μ_B$] that are orthogonally aligned with the small Re moments [$0.22(4)$ $μ_B$]. $Ab$-initio electronic structure calculations show that the strong spin-orbit coupling for Re $5d$ electrons combined with a relatively modest on-site Coulomb repulsion ($U_{eff}^{Re} \gtrsim 0.6$ eV) is sufficient to render this material insulating. This is a rare example of spin-orbit assisted Mott insulator outside the realm of iridates, with remarkable magnetic properties.

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A. S. Cavichini, M. T. Orlando, J. B. Depianti, J. L. Passamai Jr., F. Damay, F. Porcher, E. Granado. 2018-02-08. Exotic Magnetism and Spin-Orbit Assisted Mott Insulating State in a $3d-5d$ Double Perovskite. https://doi.org/10.1103/physrevb.97.054431

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