We report photoemission measurements on highly textured polycrystalline samples of Bi1.8Pb0.4Sr2Ca2Cu3O10+δ (Bi-2223, Tc=104 K). High-resolution data show a superconducting gap opening below Tc. The gap-spectrum line shape suggests an anisotropic gap structure in the Brillouin zone. The maximum gap in Bi-2223 is estimated to be 29 meV so that 2Δ/kTc∼6.5, somewhat larger than the reduced gap in Bi2Sr2CaCu2O8 (Bi-2212). A spectral dip feature is observed at 72 meV in the superconducting state. The results are compared with angle-resolved experiments on Bi-2212 single crystals.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics