Signature of multigap nodeless superconductivity in fluorine-doped NdFeAsO

Article

关键词: HIGH-TEMPERATURE SUPERCONDUCTIVITY;    IRON-BASED SUPERCONDUCTORS;    LAYERED SUPERCONDUCTOR;    PENETRATION DEPTH;    CRITICAL-FIELD;    DEPENDENCE;   

DOI  :  10.1103/PhysRevB.96.100503

来源: SCIE

【 摘 要 】

We investigate the temperature dependence of the lower critical field H-c1(T), the field at which vortices penetrate into the sample, of a high-quality fluorine-doped NdFeAsO single crystal under static magnetic fields H parallel to the c axis. The temperature dependence of the first vortex penetration field has been experimentally obtained and pronounced changes of the H-c1(T) curvature are observed, which are attributed to the multiband superconductivity. Using a two-band model with s-wave-like gaps, the temperature dependence of the lower critical field H-c1(T) can be well described. These observations clearly show that the superconducting energy gap in fluorine-doped NdFeAsO is nodeless. The values of the penetration depth at T = 0 K have been determined and confirm that the pnictide superconductors obey an Uemura-style relationship between T-c and lambda(ab)(0)(-2).

【 授权许可】

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