Electronic Raman continuum for ${\mathrm{YBa}}_2$${\mathrm{Cu}}_3$${\mathrm{O}}_{7\mathrm{-}\mathrm{\delta }}$: Effects of inelastic scattering and interband transitions

The electronic Raman continuum in ${\mathrm{YBa}}_2$ ${\mathrm{Cu}}_3$ ${\mathrm{O}}_7$ is calculated in a model which takes into account strong inelastic scattering and interband transitions. The ab-plane polarized continuum contains a large contribution from interband processes and does not depend strongly on temperature and the inelastic scattering strength. The in-plane anisotropy is determined by the interband transitions rather than by the anisotropy of the Fermi surface. The ZZ continuum can be crudely described within a single-band model with inelastic scattering and is very dependent on the relaxation rates of inelastic scattering. The nature of the oxygen-deficiency dependence of the Raman spectra is also commented upon.