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arXiv · 1011.5022

Synthesis of ErFeAsO-based superconductors by hydrogen doping method

Parasharam M. Shirage·Kiichi Miyazawa·Kunihiro Kihou·Chul-Ho Lee·Hijiri Kito·Kazuyasu Tokiwa·Yasumoto Tanaka·Hiroshi Eisaki·Akira Iyo
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Abstract

Here we demonstrate the technique to stabilize the ErFeAsO-based superconductor with the smallest lattice constants in LnFeAsO1-y (Ln = lanthanide) series using hydrogen doping method. Polycrystalline samples were synthesized by heating pellets with nominal compositions of ErFeAsO1-y (1-y = 0.75 ~ 0.95) sandwiched between pellets of LaFeAsO0.8H0.8 compositions at 1100 °C under a pressure of 5.0 - 5.5 GP. The sample with lattice constants of a = 3.8219 Å and c = 8.2807 Å shows the highest superconducting critical temperatures (Tc) of 44.5 K and 41.0 K determined by onset transitions of resistivity and susceptibility, respectively. We discuss phase diagram of Ln dependence of Tc in LnFeAsO-based superconductors.

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Parasharam M. Shirage, Kiichi Miyazawa, Kunihiro Kihou, Chul-Ho Lee, Hijiri Kito, Kazuyasu Tokiwa, Yasumoto Tanaka, Hiroshi Eisaki, Akira Iyo. 2010-11-23. Synthesis of ErFeAsO-based superconductors by hydrogen doping method. https://doi.org/10.1209/0295-5075%2F92%2F57011

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