Electron-phonon coupling induced pseudogap and the superconducting transition inBa0.67K0.33BiO3

2001/06/04 by A. Chainani, T. Yokoya, T. Kiss +5 · 1 citation
Materials Science · Physics and Astronomy · #Electronic and Structural Properties of Oxides #Iron-based superconductors research #Physics of Superconductivity and Magnetism #cond-mat.supr-con

paper · pdf · doi:10.1103/physrevb.64.180509

5 pages with 4 figures, submitted to Phys. Rev. Lett

arxiv created 2001/06/04 · openalex publication_date 2001/10/18 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28

Abstract

We study the single-particle density of states (DOS) across the superconducting transition (T_c=31K) in single-crystal Ba_0.67K_0.33BiO₃ using ultrahigh resolution angle-integrated photoemission spectroscopy. The superconducting gap opens with a pileup in the DOS, \ensuremathΔ(5.3K)=5.2meV and 2\ensuremathΔ(0)/k_BT_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 (\ensuremath∼70 meV). The results indicate electron-phonon coupling induces a pseudogap in Ba_0.67K_0.33BiO₃.

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