Magnetism and electronic structure of La2ZnIrO6and La2MgIrO6: CandidateJeff=12Mott insulators

• DOI: 10.1103/physrevb.87.155136
• Publication Date: 2013-04-22T10:27:18Z
• Authors: Guixin Cao; Alaska Subedi; S. Calder; J.-Q. Yan; Jieyu Yi; Zheng Gai; Lekhanath Poudel; David J. Singh; Mark D. Lumsden; A. D. Christianson; Brian C. Sales; David Mandrus
• Keywords: Magnetism

We study experimentally and theoretically the electronic magnetic properties of two insulating double perovskites that show similar atomic structure but different properties. In magnetization measurements, La${}_{2}$ZnIrO${}_{6}$ displays weak ferromagnetic behavior below 7.5 K, whereas La${}_{2}$MgIrO${}_{6}$ shows antiferromagnetic ${T}_{N}$ $=$ 12 K. Electronic calculations find observed in is fact due to canted antiferromagnetism. The also predict La${}_{2}$MgIrO${}_{6}$, intriguingly, this was not observed. Neutron diffraction measurements confirm essentially both systems lack sensitivity resolve small (0.22${\ensuremath{\mu}}_{\mathrm{B}}$/Ir) component La${}_{2}$ZnIrO${}_{6}$. Overall, results presented here indicate crucial role spin-orbit coupling (SOC) on-site Coulomb repulsion on magnetic, transport, thermodynamic compounds. compounds, like Sr${}_{2}$IrO${}_{4}$, are ${J}_{\mathrm{eff}}$ 1/2 Mott insulators. Our present findings suggest provide a new playground interplay between SOC 5d transition-metal oxide.