We analyze the time-domain optical response of quantum well (QW) media in the quasiequilibrium approximation. The resulting macroscopic polarization can be expressed as a convolution integral that permits a simple and efficient numerical implementation for its use in dynamical modeling. As a practical example, the resulting polarization is used in conjunction with a travelling-wave model (TWM) for analyzing saturable absorption as a pulse propagates in a waveguide that incorporates an unpumped QW in its core. Frequency-selective saturable absorption and pulse distortion are observed.

Peer reviewed