We have performed angle-resolved photoemission spectroscopy of Cu xBi2Se3 as a function of Cu doping (x=0.0-0.25) to investigate the doping-induced evolution of the electronic structure. We found that the topological surface state is preserved even in the heavy-doping region (x = 0.25), indicative of the robustness of the surface state against doping and impurities. The estimated carrier concentration is far smaller than that expected from a simple intercalation picture, and saturates at x∼0.1 where superconductivity emerges. This indicates that the carrier concentration responsible for superconductivity is dominated by a subtle balance between two competing processes of electron and hole doping.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2012 Mar 12|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics