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arXiv · 1404.2738

Synthesis and physical properties of Ca1-xRExFeAs2 with RE = La ~ Gd

Alberto Sala·Hiroyuki Yakita·Hiraku Ogino·Tomoyuki Okada·Akiyasu Yamamoto·Kohji Kishio·Shigeyuki Ishida·Akira Iyo·Hiroshi Eisaki·Masaya Fujioka·Yoshihiko Takano·Marina Putti·Jun-ichi Shimoyama
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Abstract

Synthesis of a series of layered iron arsenides Ca1-xRExFeAs2 (112) was attempted by heating at 1000 C under a high-pressure of 2 GPa. The 112 phase successfully forms with RE = La, Ce, Nd, Sm, Eu and Gd, while Tb, Dy and Ho substituted and RE free samples does not contain the 112 phase. The Ce, Nd, Sm, Eu and Gd doped Ca1-xRExFeAs2 are new compounds. All of them exhibit superconducting transition except for the Ce doped sample. The behaviour of the critical temperature, with the RE ionic radii have been investigated.

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Alberto Sala, Hiroyuki Yakita, Hiraku Ogino, Tomoyuki Okada, Akiyasu Yamamoto, Kohji Kishio, Shigeyuki Ishida, Akira Iyo, Hiroshi Eisaki, Masaya Fujioka, Yoshihiko Takano, Marina Putti, Jun-ichi Shimoyama. 2014-04-10. Synthesis and physical properties of Ca1-xRExFeAs2 with RE = La ~ Gd. https://doi.org/10.7567/apex.7.073102

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