Strain dependence of valence band structure and intersubband transitions in coupled quantum wells

We have calculated the structure of the valence bands and its dependence on strain in a lattice mismatched quantum well, and in double quantum wells with equal and unequal well thicknesses. We have used the 4×4 Luttinger-Kohn Hamiltonian and the envelope function approximation. Further the character of the strain dependence of optical transitions in valence band was analysed in all of these structures. It has been found that the strain dependence of the valence band structure and optical momentum matrix elements is stronger in the double quantum well than in the single quantum well. This result is potentially useful in valence band engineering and device applications.