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arXiv · 1509.06486

Enhancement of Tc in BiS2 based superconductors NdO0.7F0.3BiS2 by substitution of Pb for Bi

S. Demura·Y. Fujisawa·S. Otsuki·R. Ishio·Y. Takano·H. Sakata
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Abstract

We succeed in enhancement of a superconducting transition temperature (Tc) for NdO0.7F0.3BiS2 single crystal by partial substitution of Pb for Bi. The Tc increases with increasing Pb concentration until 6%. The maximum Tczero is 5.6 K, which is the highest value among BiS2 based superconductors synthesized under an ambient pressure. Pb substitution for Bi induces lattice shrinkage along the c axis. These results reflect that superconductivity in this system is responsive to the lattice strain.

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S. Demura, Y. Fujisawa, S. Otsuki, R. Ishio, Y. Takano, H. Sakata. 2015-11-16. Enhancement of Tc in BiS2 based superconductors NdO0.7F0.3BiS2 by substitution of Pb for Bi. https://doi.org/10.1016/j.ssc.2015.09.002

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