Muon spin rotation measurements on RbEuFe$_{4}$As$_{4}$ under pressure

S. Holenstein; B. Fischer; Y. Liu; N. Barbero; G. Simutis; Z. Shermadini; M. Elender; P. K. Biswas; R. Khasanov; A. Amato; T. Shiroka; H. -H. Klauss; E. Morenzoni; G. -H. Cao; D. Johrendt; H. Luetkens

arXiv · 1911.04325

Muon spin rotation measurements on RbEuFe$_{4}$As$_{4}$ under pressure

S. Holenstein·B. Fischer·Y. Liu·N. Barbero·G. Simutis·Z. Shermadini·M. Elender·P. K. Biswas·R. Khasanov·A. Amato·T. Shiroka·H. -H. Klauss·E. Morenzoni·G. -H. Cao·D. Johrendt·H. Luetkens

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Abstract

We report muon spin rotation and magnetization measurements on the magnetic superconductor RbEuFe$_{4}$As$_{4}$ under hydrostatic pressures up to 3.8 GPa. At ambient pressure, RbEuFe$_{4}$As$_{4}$ exhibits a superconducting transition at $T_{c} \approx$ 36.5 K and a magnetic transition at $T_{m} \approx$ 15 K below which the magnetic and the superconducting order coexist. With increasing pressure, $T_{c}$ decreases while $T_{m}$ and the ordered Eu magnetic moment increase. In contrast to iron-based superconductors with ordering Fe moments, the size of the ordered Eu moment is not proportional to $T_{m}$. The muon spin rotation signal is dominated by the magnetic response impeding the determination of the superconducting properties.

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S. Holenstein, B. Fischer, Y. Liu, N. Barbero, G. Simutis, Z. Shermadini, M. Elender, P. K. Biswas, R. Khasanov, A. Amato, T. Shiroka, H. -H. Klauss, E. Morenzoni, G. -H. Cao, D. Johrendt, H. Luetkens. 2019-11-11. Muon spin rotation measurements on RbEuFe$_{4}$As$_{4}$ under pressure. https://arxiv.org/abs/1911.04325

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