c-axis electronic Raman scattering in Bi2Sr2CaCu2O8+delta

We report on the c-axis-polarized electronic Raman scattering of Bi2Sr2CaCu2O8+delta single crystals with various oxygen concentrations. In the normal state, a resonant electronic continuum extends to 1.5 eV and gains significant intensity as the incoming photon energy increases. Below T-c, a superconductivity-induced 2 Delta peak is observed for omega 80 meV and the 2 Delta/k(B)T(c) value increases with decreasing hole doping. In particular, this A(Ig) 2 Delta peak energy, which is higher than that seen with inplane polarizations for all doping levels studied, signifies distinctly different dynamics of quasiparticles coated with out-of-plane polarization.