Superconductivity in a ferromagnetic layered compound

Article

关键词: LARKIN-OVCHINNIKOV STATE;    LOW-DIMENSIONAL SUPERCONDUCTORS;    PARALLEL MAGNETIC-FIELDS;    FULDE-FERRELL STATE;    PHASE FLUCTUATIONS;    DC MAGNETIZATION;    RUSR2GDCU2O8;    COEXISTENCE;    GD;   

DOI  :  10.1103/PhysRevB.62.14541

来源: SCIE

【 摘 要 】

We examine superconductivity in layered systems with large Fermi-surface splitting due to coexisting ferromagnetic layers. In particular, the hybrid ruthenate-cuprate compound RuSr2GdCu2O8 is examined on the coexistence of the superconductivity and the ferromagnetism. We calculate critical fields of the superconductivity taking into account the Fulde-Ferrell-Larkin-Ovchinnikov state in a model with realistic Fermi surfaces the shapes of which are similar to those obtained by a band calculation. It is shown that the critical field is enhanced markedly due to nearly flat areas of the Fermi surfaces and the van I-love singularity points in the momentum space. The result of the critical field is very large for realistic parameters, and seems to support the coexistence in a microscopic scale. We also clarify the direction of the spatial oscillation of the order parameter, which may be observed by scanning tunneling microscope experiments.

【 授权许可】

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