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arXiv · 1404.6489

Effect of external pressure on the magnetic properties of $R$CoAsO ($R$ = La, Pr, Sm): a $\mu$SR study

G. Prando·S. Sanna·R. Khasanov·A. Pal·E. M. Brüning·M. Mazzani·V. P. S. Awana·B. Büchner·R. De Renzi
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Abstract

We report on a detailed investigation of the itinerant ferromagnets LaCoAsO, PrCoAsO and SmCoAsO performed by means of muon spin spectroscopy upon the application of external hydrostatic pressures $p$ up to $2.4$ GPa. These materials are shown to be magnetically hard in view of the weak dependence of both critical temperatures $T_{C}$ and internal fields at the muon site on $p$. In the cases $R$ = La and Sm, the behaviour of the internal field is substantially unaltered up to $p = 2.4$ GPa. A much richer phenomenology is detected in PrCoAsO instead, possibly associated with a strong $p$ dependence of the statistical population of the two different crystallographic sites for the muon. Surprisingly, results are notably different from what is observed in the case of the isostructural compounds $R$CoPO, where the full As/P substitution is already inducing a strong chemical pressure within the lattice but $p$ is still very effective in further affecting the magnetic properties.

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G. Prando, S. Sanna, R. Khasanov, A. Pal, E. M. Brüning, M. Mazzani, V. P. S. Awana, B. Büchner, R. De Renzi. 2014-04-25. Effect of external pressure on the magnetic properties of $R$CoAsO ($R$ = La, Pr, Sm): a $\mu$SR study. https://doi.org/10.1016/j.jpcs.2015.01.012

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