Local suppression of the superfluid density of PuCoGa5 by strong onsite disorder

Article

关键词: D-WAVE SUPERCONDUCTORS;    HIGH-T-C;    FIELD PENETRATION DEPTH;    MUON SPIN RELAXATION;    UNCONVENTIONAL SUPERCONDUCTORS;    CUPRATE SUPERCONDUCTORS;    TRANSITION-TEMPERATURE;    IMPURITY-SCATTERING;    ORDER-PARAMETER;    ZN-SUBSTITUTION;   

DOI  :  10.1103/PhysRevB.84.134510

来源: SCIE

【 摘 要 】

We present superfluid density calculations for the unconventional superconductor PuCoGa5 by solving the real-space Bogoliubov-de Gennes equations on a square lattice within the Swiss-cheese model in the presence of strong onsite disorder. We find that, despite strong electronic inhomogeneity, one can establish a one-to-one correspondence between the local maps of the density of states, superconducting order parameter, and superfluid density. In this model, strong onsite impurity scattering punches localized holes into the fabric of d-wave superconductivity similar to a Swiss cheese. Already, a two-dimensional impurity concentration of n(imp) = 4% gives rise to a pronounced short-range suppression of the order parameter and a suppression of the superconducting transition temperature T-c by roughly 20% compared to its pure limit value T-c0, whereas the superfluid density rho(s) is reduced drastically by about 70%. This result is consistent with available experimental data for aged (400-day-old) and fresh (25-day-old) PuCoGa5 superconducting samples. In addition, we show that the T-2 dependence of the low-T superfluid density, a signature of dirty d-wave superconductivity, originates from a combined effect in the density of states of gap filling and gap closing. Finally, we demonstrate that the Uemuera plot of Tc versus rho(s) deviates sharply from the conventional Abrikosov-Gor'kov theory for radiation-induced defects in PuCoGa5, but follows the same trend of short-coherence-length high-T-c cuprate superconductors.

【 授权许可】

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