Enhancing superconductivity by disorder

Article

关键词: HIGH-TEMPERATURE SUPERCONDUCTORS;    C CUPRATE SUPERCONDUCTORS;    DIRTY SUPERCONDUCTORS;    INSULATOR TRANSITION;    COHERENCE LENGTH;    ZN-SUBSTITUTION;    SUPPRESSION;    IMPURITIES;    ALLOYS;    STATE;   

DOI  :  10.1103/PhysRevB.98.184510

来源: SCIE

【 摘 要 】

We study two mechanisms for enhancing the superconducting mean-field transition temperature T-c by nonmagnetic disorder in both conventional (sign-preserving gaps) and unconventional (sign-changing gaps) superconductors (SCs). In the first scenario, relevant to multiband systems of both conventional and unconventional SCs, we demonstrate how favorable density-of-states enhancements driven by resonant states in off-Fermi-level bands lead to significant enhancements of T-c in the condensate formed by the near-Fermi-level bands. The second scenario focuses on systems close to localization where random disorder-generated local density-of-states modulations cause a boosted T-c even for conventional single-band SCs. We analyze the basic physics of both mechanisms within simplified models, and we discuss the relevance to existing materials.

【 授权许可】

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