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arXiv · 0904.2618

EuFe$_2$As$_2$ under high pressure: an antiferromagnetic bulk superconductor

Taichi Terashima·Motoi Kimata·Hidetaka Satsukawa·Atsushi Harada·Kaori Hazama·Shinya Uji·Hiroyuki S. Suzuki·Takehiko Matsumoto·Keizo Murata
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Abstract

We report the ac magnetic susceptibility $χ_{ac}$ and resistivity $ρ$ measurements of EuFe$_2$As$_2$ under high pressure $P$. By observing nearly 100% superconducting shielding and zero resistivity at $P$ = 28 kbar, we establish that $P$-induced superconductivity occurs at $T_c \sim$~30 K in EuFe$_2$As$_2$. $ρ$ shows an anomalous nearly linear temperature dependence from room temperature down to $T_c$ at the same $P$. $χ_{ac}$ indicates that an antiferromagnetic order of Eu$^{2+}$ moments with $T_N \sim$~20 K persists in the superconducting phase. The temperature dependence of the upper critical field is also determined.

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Taichi Terashima, Motoi Kimata, Hidetaka Satsukawa, Atsushi Harada, Kaori Hazama, Shinya Uji, Hiroyuki S. Suzuki, Takehiko Matsumoto, Keizo Murata. 2009-06-17. EuFe$_2$As$_2$ under high pressure: an antiferromagnetic bulk superconductor. https://doi.org/10.1143/jpsj.78.083701

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