We study the single-particle density of states (DOS) across the superconducting transition (Tc=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, Δ(5.3 K) = 5.2 meV and 2Δ(0)/kBTc = 3.9. In addition, we observe a pseudogap below and above Tc, occurring as a suppression in intensity over an energy scale up to the breathing mode phonon (∼70 meV). The results indicate electron-phonon coupling induces a pseudogap in Ba0.67K0.33BiO3.
|Number of pages||4|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - Nov 1 2001|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics