The results of Raman scattering from superconducting gap excitations in the high Tc compounds YBa2Cu3O7-δ and Bi2Sr2CaCu2O8+Δ are compared. In the normal state, both materials exhibit strong electronic interband scattering which manifests itself as a broad background continuum having both A1g and B1g symmetry components. At low temperatures a redistribution of this electronic scattering occurs, indicative of the formation of a superconducting gap in these compounds. The two symmetries exhibit distinct redistribution, however, denoting strong anisotropy. At temperatures well below Tc, both compounds exhibit residual low-energy scattering, a feature suggestive of the coexistence of normal electrons and superconducting quasi-particles.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics
- Electrical and Electronic Engineering