ARPES study of the superconducting gap and pseudogap in Bi2Sr2CaCu2O8+x

In this paper, we review some of our ARPES results on the superconducting a nd pseudo gaps in Bi2Sr2CaCu2O8+x. We find that optimally and overdoped sam ples exhibit a d-wave gap, which closer at the same temperature, T-c, for a ll k points. In underdoped samples, a leading edge gap is Found up to a tem perature T* > T-c. We find that T* scales with the maximum low temperature gap, increasing as the doping is reduced. The momentum dependence of the ps eudogap is similar to that of the superconducting gap: however, the pseudog ap closes at different temperatures for different k points. (C) 1998 Publis hed by Elsevier Science Ltd. All rights reserved.