Superconductivity in black phosphorus and the role of dynamical screening

Article

关键词: DENSITY-FUNCTIONAL THEORY;    TRANSITION-TEMPERATURE;    ANOMALOUS SUPERCONDUCTIVITY;    PHASE-TRANSITION;    BAND-STRUCTURE;    SYSTEMS;    ENERGY;   

DOI  :  10.1103/PhysRevB.105.174513

来源: SCIE

【 摘 要 】

Simple cubic phosphorus exhibits superconductivity with a maximum T-c of up to 12 K under pressure. The pressure dependence of T-c cannot be consistently explained with a simple electron-phonon mechanism, which has stimulated investigations into the role of electronic correlations and plasmonic contributions. Here we solve the gap equation of density functional theory for superconductors using different electron-electron and electron-phonon contributions to the kernel. We find that the phonon contribution alone yields an overestimation of T-c, while the addition of the static electronic contribution results in an underestimation. Taking into account the full frequency dependence of the screened interaction, the one-shot GW approximation predicts T-c values in good agreement with the experiments in the pressure range appropriate for the cubic phase. We also explore the use of quasiparticle bands in the calculation of the electronic and phononic kernels, and show that this modification significantly improves T-c in the high-pressure region.

【 授权许可】

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