Superconducting gap and pseudogap in Bi-2212

Abstract We present results of Raman scattering experiments in differently doped Bi 2 Sr 2 (Ca x Y 1− x )Cu 2 O 8+ δ (Bi-2212) single crystals. Below T c the spectra show pair–breaking features in the whole doping range reflecting a d x 2 – y 2 order parameter. In the normal state between T c and T ∗ ≃200 K we find signatures for a pseudogap in B 2g symmetry which disappear above optimal doping.