Doping and temperature dependence of the mass enhancement observed in the cuprate Bi2Sr2CaCu2O8+delta - art. no. 177007

High-resolution photoemission is used to study the electronic structure of the cuprate superconductor, Bi2Sr2CaCu2O8+delta, as a function of hole dopi ng and temperature. A kink observed in the band dispersion in the nodal lin e in the superconducting state is associated with coupling to a resonant mo de observed in neutron scattering. From the measured real part of the self- energy it is possible to extract a coupling constant which is largest in th e underdoped regime, then decreasing continuously into the overdoped regime .