Electron-phonon coupling induced pseudogap and the superconducting transition in Ba0.67K0.33BiO3

Article

关键词: HIGH-TEMPERATURE SUPERCONDUCTIVITY;    METAL-INSULATOR-TRANSITION;    STRUCTURAL PHASE-DIAGRAM;    DENSITY-OF-STATES;    X-RAY-ABSORPTION;    HIGH-TC;    SPIN-GAP;    BA1-XKXBIO3;    PHOTOEMISSION;    BA0.6K0.4BIO3;   

DOI  :  10.1103/PhysRevB.64.180509

来源: SCIE

【 摘 要 】

We study the single-particle density of states (DOS) across the superconducting transition (T-c = 31 K) in single-crystal Ba0.67K0.33BiO3 using ultrahigh resolution angle-integrated photoemission spectroscopy. The superconducting gap opens with a pileup in the DOS, Delta (5.3 K) = 5.2 meV and 2 Delta (0)/k(B)T(c) = 3.9. In addition, we observe a pseudogap below and above T-c occurring as a suppression in intensity over an energy scale up to the breathing mode phonon (similar to 70 meV). The results indicate electron-phonon coupling induces a pseudogap in Ba0.67K0.33BiO3.

【 授权许可】

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