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arXiv · 1504.03962

Phase diagram of pyrochlore iridates: all-in-all-out magnetic ordering and non-Fermi liquid properties

Hiroshi Shinaoka·Shintaro Hoshino·Matthias Troyer·Philipp Werner
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Abstract

We study the prototype 5d pyrochlore iridate Y2Ir2O7 from first principles using the local density approximation and dynamical mean-field theory (LDA+DMFT). We map out the phase diagram in the space of temperature, onsite Coulomb repulsion U, and filling. Consistent with experiments, we find that an all-in-all-out ordered insulating phase is stable for realistic values of U. The trigonal crystal field enhances the magnetic moments of the jeff=1/2 doublet, and strong inter-band correlations are induced by the Coulomb interaction, which indicates that a three-band description is important. We demonstrate a substantial band narrowing in the paramagnetic metallic phase and non-Fermi liquid behavior in the electron/hole doped system originating from long-lived quasi-spin moments induced by nearly flat bands.

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Hiroshi Shinaoka, Shintaro Hoshino, Matthias Troyer, Philipp Werner. 2015-04-15. Phase diagram of pyrochlore iridates: all-in-all-out magnetic ordering and non-Fermi liquid properties. https://doi.org/10.1103/physrevlett.115.156401

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