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

TL;DR

This study demonstrates that a disordered Ca1.5La0.5MnRuO6 compound exhibits near-room-temperature ferrimagnetism and half-metallicity, challenging the notion that such properties require ordered structures, with potential implications for spintronic applications.

Contribution

It reveals that disordered double-perovskites can exhibit ferrimagnetism and half-metallicity at near-room temperatures, expanding the understanding of structure-property relationships.

Findings

Disordered Ca1.5La0.5MnRuO6 shows ferrimagnetism near room temperature.

The material exhibits half-metallic conductivity with significant tunneling magnetoresistance.

The properties are comparable to ordered double-perovskites despite disorder.

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.