Microscopic Modeling of intersubband optical processes in type II semiconductor quantum wells: Linear absorption

Intersubband absorption spectra are analyzed using the density matrix theory under the second Born approximation. The intersubband semiconductor Bloch equations are derived from the first principles including electron-electron and electron-longitudinal optical phonon interactions, whereas electron-interface roughness scattering is considered using Ando's theory. A spurious-states-free 8-band k.p Hamiltonian is used, in conjunction with the envelope function approximation to calculate the electronic band structure self-consistently for type II InAs/AlSb multiple quantum well structures. We demonstrate the interplay of various physical processes in the absorption spectra in the mid-infrared frequency range.