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arXiv · 0908.2280

Pressure-Induced Antiferromagnetic Bulk Superconductor EuFe$_2$As$_2$

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

We present the magnetic and superconducting phase diagram of EuFe$_2$As$_2$ for $B \parallel c$ and $B \parallel ab$. The antiferromagnetic phase of the Eu$^{2+}$ moments is completely enclosed in the superconducting phase. The upper critical field vs. temperature curves exhibit strong concave curvatures, which can be explained by the Jaccarino-Peter compensation effect due to the antiferromagnetic exchange interaction between the Eu$^{2+}$ moments and conduction electrons.

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Taichi Terashima, Hiroyuki S. Suzuki, Megumi Tomita, Motoi Kimata, Hidetaka Satsukawa, Atsushi Harada, Kaori Hazama, Takehiko Matsumoto, Keizo Murata, Shinya Uji. 2009-08-17. Pressure-Induced Antiferromagnetic Bulk Superconductor EuFe$_2$As$_2$. https://doi.org/10.1016/j.physc.2009.10.064

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