Fano Resonance in a Coupled Electron-Phonon System

Raman light scattering with excitation of electron-hole continuum and a phonon is investigated theoretically. The effect of a surface and screening of the electron-photon coupling and of the deformation potential as a result of the Coulomb interaction of the electrons is taken into account. The parameters of the 340 cm$\text{}^{-1}$ resonance line in superconducting YBaCuO are estimated by comparing with experimental data.