Absorption anisotropy for lattice matched GaAs/AlGaAs multiple quantum well structures under external anisotropic biaxial strain: Compression along [110] and tension along [(1)over-bar10]

We report theoretical studies on the optical absorption anisotropy for exci tonic transitions in lattice-matched GaAs/AlGaAs multiple quantum well (MQW ) structures under simultaneous compression and tension applied along the [ 110] and [(1) over bar 10] directions of the MQW, respectively. The analyse s are based on a model that includes both the 4 x 4 k.p Hamiltonian and the strain Hamiltonian. The wave functions, found by solving the eigenvalue eq uations, are used to calculate the dipole matrix elements for excitonic tra nsitions and evaluate the anisotropic absorption properties. The effect of variation of parameters such as well width and barrier height on the perfor mance of the strained GaAs/AlGaAs MQW electroabsorption modulators is discu ssed.