Analysis of QW with strained thin layers for polarization insensitive optical amplifiers

A practical approach to achieve the polarization insensitive optical gain a t 1.55 mu m with quantum well (QW) in which thin and highly tensile straine d layers are embedded is numerically investigated. The precise band structu res and the optical gain characteristics of the structure are calculated. C omparing with the results obtained from the tight-binding model, we conclud ed that the k p method based on the envelop function approximation is still valid for such complicated structures like delta-strained quantum wells.