We report angle-resolved photoemission results on Bi2Sr2Ca1-xDyxCu2O 8+δ and oxygen depleted Bi2Sr2CaCu2O8+δ investigating the electronic structure changes above Tc in materials with hole doping levels ranging from insulating to slightly overdoped. Near optimal hole doping, the Fermi surface is large and consistent with band calculations. In underdoped samples with Tc of 60-70 K, portions of this Fermi surface are not seen. This change is related to the opening of an energy gap near (π 0) above Tc.
ASJC Scopus subject areas
- Physics and Astronomy(all)