The optimization of optical gain in the intersubband quantum well laser

A systematic procedure is described for the maximization of gain in optical ly pumped intersubband lasers, via optimal tailoring of the quantum well pr ofile. The procedure relies on using the inverse spectral theory, allowing one to shift the bound states as desired, and additionally to make the isos pectral reshaping of the well, with the eventual aim of finding the best co mbination of those optical dipole and electron-phonon scattering matrix ele ments which are relevant for the laser gain. Example design is presented fo r a laser based on the AlxGa1-xAs system, and the band nonparabolicity is a ccounted for in the final design. (C) 2000 American Institute of Physics. [ S0021-8979(00)01511-5].