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arXiv · 2410.01980

Near-room-temperature ferrimagnetism and half-metallicity in disordered Ca1.5La0.5MnRuO6

A. G. Silva·R. B. Pontes·M. Boldrin·H. V. S. Pessoni·L. S. I. Veiga·J. R. Jesus·H. Fabrelli·A. R. C. Gonzaga·E. M. Bittar·L. Bufaiçal
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Abstract

The electron spin polarization on half-metallic double-perovskites is usually conditioned to the ordered rock-salt arrangement of the transition-metal ions along the lattice. In this work, we investigate a polycrystalline sample of the Ca1.5La0.5MnRuO6 compound by employing x-ray powder diffraction, high resolution transmission electron microscopy, x-ray absorption and magnetic circular dichroism at the Mn-L2,3 and Ru-M2,3 edges, magnetometry, electrical transport and first principles calculations in order to show that this is a fully disordered material exhibiting near room temperature ferrimagnetism and half-metallic conductivity, with significant intergrain tunneling magnetoresistance. These unprecedented results are compared to those of archetypical ordered double-perovskites, and discussed in terms of the Mn and Ru valences and their orbital hybridization.

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A. G. Silva, R. B. Pontes, M. Boldrin, H. V. S. Pessoni, L. S. I. Veiga, J. R. Jesus, H. Fabrelli, A. R. C. Gonzaga, E. M. Bittar, L. Bufaiçal. 2024-10-02. Near-room-temperature ferrimagnetism and half-metallicity in disordered Ca1.5La0.5MnRuO6. https://doi.org/10.1103/physrevb.110.144415

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