Angle-resolved photoemission study of Bi2Sr2Ca1−xYxCu2O8(x=0.0, 0.2, 0.4, 0.6) single crystals

Abstract Angle-Resolved photoemission measurements were performed on a series of Bi 2 Sr 2 Ca 1−x Y x Cu 2 O 8 (x=0.0, 0.2, 0.4, and 0.6) single crystals. It was found that hole-doping in an insulator (x=0.6) produces new electronic states in the charge-transfer gap and the density of new states increases with hole- concentration. In this over-doped region (x=0.0 and 0.2), a slight rigid shift of bands crossing the Fermi level was observed. This suggests that a rigid-band picture may be recovered in the over-doped region.