Band-gap renormalization in quasi-two-dimensional systems induced by many-body electron-electron and electron-phonon interactions

Dynamical electron-electron and electron-phonon interaction corrections to the conduction- and valence-band edges of photoexcited quasi-two-dimensional quantum wells are calculated for arbitrary quantum-well widths and electron-hole densities. Band-gap renormalization, when expressed in Rydberg units, is shown to be an approximate universal function of the effective $r_s$ parameter and the well width.