Nb V ò & ÿ; c  \ ¥ (Ru,Nb.Sn)Sr

Effect of Nb Doping on the Superconducting Properties of (Ru,Nb,Sn)Sr

EuCu

O

Ho Keun Lee

Department of Physics, Kangwon National University, Chuncheon 24341, Korea (Received 4 August 2015 : revised 12 August 2015 : accepted 13 August 2015)

Polycrystalline samples of (Ru1−xNbx) Sr2EuCu2Ozand (Ru0.8−xNbxSn0.2) Sr2EuCu2Ozwith 0

≤ x ≤ 0.4 were synthesized by using a solid state-state reaction method. The phase formation and the physical properties were investigated by means of X-ray diffraction and transport measurements.

Contrary to the observation of no superconductivity in Sn-free Nb-doped (Ru1−xNbx) Sr2EuCu2Oz

samples with x ≥ 0.2, a superconducting transition behavior was observed in the (Ru0.8−xNbxSn0.2) Sr2EuCu2Oz samples, and an onset superconducting transition temperatures Tc, of about 29 K and 35 K were observed for the x = 0.2 and 0.4 samples, respectively. The superconducting behaviors induced by Nb and Sn co-doping are discussed in conjunction with the changes in the hole concentration and the structure.

PACS numbers: 74.72.-h, 74.70.Pq, 74.62.Dh, 74.25.-q

Keywords: (Ru,Nb,Sn)Sr2EuCu2Oz, Nb/Sn co-doping, Superconductivity

Nb V ò & ÿ; c  Â \ ¥ (Ru,Nb.Sn)Sr

EuCu

O

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PACS numbers: 74.72.-h, 74.70.Pq, 74.62.Dh, 74.25.-q

Keywords: (Ru,Nb,Sn)Sr2EuCu2Oz, Nb/Sn 1lxr •¸iç, œí„•¸ :£¤$í

∗E-mail: hklee221@kangwon.ac.kr

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

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