Quasiparticle Formation and Decay in Pulsed Photoexcitation of Disordered Semiconductors

The quasiparticle states in strongly illuminated semiconductors are light hybridized electron and hole states, Galickii quasiparticles. Their properties, especially if they are photoexcited at small detunings, may be rather complex. A protracted formation period is followed by quantum beats of two decaying resonances corresponding to both sides of the hybridization gap. On an example of elastic scattering on an alloy disorder, these phenomena are demonstrated and analyzed in terms of poles of the retarded Green function and the corresponding residuals.