What happened at 19% doping in Bi2212: an ARPES perspective*

In the hole-doped cuprate superconductors, the special doping p = 0.19 has attracted considerable research interest. Various anomalies have been observed at this doping and associated with fascinating physics, for example the change from small to large Fermi surface, the termination of the pseudogap, the recovery of coherence, and the possibility of a quantum critical point. In this talk we present a systematic ARPES study across 84 temperature-doping points in Bi2212 near p = 0.19. The results provide important insights about the nature of this special doping and the phenomenology of the cuprates.