Enhanced Superconductivity up to 43 K by P/Sb Doping of Ca1-xLaxFeAs2

Kazutaka Kudo; Tasuku Mizukami; Yutaka Kitahama; Daisuke Mitsuoka; Keita Iba; Kazunori Fujimura; Naoki Nishimoto; Yuji Hiraoka; Minoru Nohara

doi:10.7566/jpsj.83.025001

arXiv · 1311.1269

Enhanced Superconductivity up to 43 K by P/Sb Doping of Ca1-xLaxFeAs2

Kazutaka Kudo·Tasuku Mizukami·Yutaka Kitahama·Daisuke Mitsuoka·Keita Iba·Kazunori Fujimura·Naoki Nishimoto·Yuji Hiraoka·Minoru Nohara

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Abstract

The effects of isovalent doping on the superconducting transition temperature Tc in novel 112-type iron arsenide Ca1-xLaxFeAs2 were studied by conducting measurements of electrical resistivity rho and magnetization M. P or Sb doping strongly enhances Tc: P-doped Ca0.84La0.16FeAs2 and Sb-doped Ca0.85La0.15FeAs2 exhibited Tc of 41 and 43 K, respectively, while Ca0.85La0.15FeAs2 without P/Sb exhibited Tc = 35 K. These observations will give a hint for further enhancing Tc of rare-earth doped Ca-Fe-As systems.

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Kazutaka Kudo, Tasuku Mizukami, Yutaka Kitahama, Daisuke Mitsuoka, Keita Iba, Kazunori Fujimura, Naoki Nishimoto, Yuji Hiraoka, Minoru Nohara. 2013-11-06. Enhanced Superconductivity up to 43 K by P/Sb Doping of Ca1-xLaxFeAs2. https://doi.org/10.7566/jpsj.83.025001

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