Investigation of orientation dependence of piezoelectric effects in strained GaAs/InGaAs quantum well laser

In this work, we report a theoretical investigation of the influence of piezoelectric on the optical transition and laser-gain in [111]-oriented GaAs/InGaAs quantum well (QW). A k.p multi-bands Hamiltonian, taking into account the band mixing and strain effect has been introduced and factorized into two 4 x 4 real matrices via a unitary transformation. The impact of the piezoelectric on the band structure and optical transition and gain is visualized under inclusion of the strain in the [111]-oriented QWs. It has been shown that the piezoelectric changes the electronic band structure and as a result the optical transition and gain decreases with the piezoelectric field by about 50% for transverse electric and magnetic modes. Spinor and wave functions distributions of the band states in the QW are also calculated. It is found that the wave function and spinor exhibit very different distribution patterns in the QWs oriented along [001]-and [1 1 1]-directions. Finally, we can predict that GaAs/InGaAs QW realized in the [001]-orientation are more convenient than QWs of [1 1 1]-orientation in most applications involving optical transitions and laser-gain for optoelectronics devices.