Exceptional suppression of flux-flow resistivity in FeSe0.4Te0.6 by back-flow from excess Fe atoms and Se/Te substitutions

Article

关键词: PENETRATION DEPTH;    DYNAMIC STRUCTURE;    SUPERCONDUCTORS;    EXCITATIONS;    VORTICES;    MOTION;   

DOI  :  10.1103/PhysRevB.91.054510

来源: SCIE

【 摘 要 】

We measured the microwave surface impedance of FeSe0.4Te0.6 single crystals with and without external magnetic fields. The superfluid density exhibited a quadratic temperature dependence, indicating a strong pair-breaking effect. The flux-flow resistivity behaved as rho(f)(B << B-c2)/rho(n) = alpha B/B-c2. The observed alpha value of approximate to 0.66 was considerably smaller than that of other Fe-based materials (alpha >= 1) and was attributed to a back-flow of superfluids remarkable in disordered superconductors. This is an observation of the back-flow phenomenon caused by an origin other than the vortex pinning in multiple-band systems.

【 授权许可】

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