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arXiv · 2003.10418

Monopole-limited nucleation of magnetism in Eu$_{2}$Ir$_{2}$O$_{7}$

Giacomo Prando·Prachi Telang·Stephen D. Wilson·Michael J. Graf·Surjeet Singh
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Abstract

We present an in-depth analysis of muon-spin spectroscopy measurements of Eu$_{2}$Ir$_{2}$O$_{7}$ under the effect of the Eu$_{1-x}$Bi$_{x}$ isovalent and diamagnetic substitution as well as of external pressure. Our results evidence an anomalously slow increase of the magnetic volume fraction upon decreasing temperature only for stoichiometric Eu$_{2}$Ir$_{2}$O$_{7}$, pointing towards highly unconventional properties of the magnetic phase developing therein. We argue that magnetism in Eu$_{2}$Ir$_{2}$O$_{7}$ develops based on the nucleation of magnetic droplets at $T_{N}$, whose successive growth is limited by the need of a continuous generation of magnetic hedgehog monopoles.

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Giacomo Prando, Prachi Telang, Stephen D. Wilson, Michael J. Graf, Surjeet Singh. 2020-03-23. Monopole-limited nucleation of magnetism in Eu$_{2}$Ir$_{2}$O$_{7}$. https://doi.org/10.1103/physrevb.101.174435

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