Angle-resolved photoemission spectroscopy is used to study the band structure of superconducting electrochemically intercalated CuxBi2Se3. We find that in these samples, the band gap at the Γ point is much larger than in pristine Bi2Se3. Comparison to the results of band structure calculations indicates that the origin of this large gap is internal stress caused by disorder created by the Cu intercalation. We suggest that the internal pressure may be necessary for superconductivity in CuxBi2Se3.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics