Theoretical studies of self-induced transparency have used the slowly varying envelope approximation with perturbative corrections. These analyses indicated that for a carrier wave of given frequency, there was a continuum of possible steady-state pulse velocities. We show that the exact steady-state solutions of the full Maxwell-Bloch equations do not share this property; instead, there is a nonperturbative selection mechanism: a carrier wave of given frequency gives rise to steady-state pulses with discrete values of the velocity only. We present analytical and numerical calculations, and suggest some experiments for the semiconductor CdS.

• Received 21 August 1990

DOI:https://doi.org/10.1103/PhysRevA.43.1549