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arXiv · 1902.03214

Anomalous lattice contraction and emergent electronic phases in Bi-doped Eu$_2$Ir$_2$O$_7$

Prachi Telang·Kshiti Mishra·Giacomo Prando·A. K. Sood·Surjeet Singh
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Abstract

We study the pyrochlore series (Eu$_{1-x}$Bi$_x$)$_2$Ir$_2$O$_7$ for $ 0 \leq x \leq 1$. We show that for small $x$, the lattice undergoes an anomalous contraction but the all-in/all-out and metal-to-insulator transitions remain robust, and the resistivity approaches a $1/T$ dependence at low-T, suggesting proximity to the Weyl semimetallic phase, as previously predicted theoretically. At the boundary between Eu$_2$Ir$_2$O$_7$ and Bi$_2$Ir$_2$O$_7$ a qualitatively different ground state emerges, which is characterized by its unusual metallic behavior and absence of magnetic ordering at least down to $0.02$ K.

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Prachi Telang, Kshiti Mishra, Giacomo Prando, A. K. Sood, Surjeet Singh. 2019-02-08. Anomalous lattice contraction and emergent electronic phases in Bi-doped Eu$_2$Ir$_2$O$_7$. https://doi.org/10.1103/physrevb.99.201112

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