Piezoelectric field-dependent optical properties of InGaAs/GaAs quantum well architecture in arbitrary crystal orientation

A numerical approach is introduced to study the optical properties of compressively strained InGaAs/GaAs quantum well (QW) architecture considering the piezoelectric (PZ) effect by solving one dimensional Schrödinger equation using finite difference method. Unitary transformation is used to modify the wave vector and strain matrix in conventional [100] crystal orientation. The simulation is carried out for conventional crystal orientations [110] and [111] as well as non-conventional orientations [113] and [131]. It is found that there is a substantial correlation between piezoelectric field and conduction and valence band energy dispersion profile. Using the shift in energy bands due to PZ field, the optical gain profile for compressively strained QW is evaluated and compared with the optical gain profile neglecting PZ field. From the MATLAB simulation results, the regular optical gains are inspected as 2630, 1720, 2720, and 2020 cm^-1 in [1 1 0], [1 1 1], [1 1 3], and [1 3 1] crystal orientations which indicates an average decrease of about 13% of peak gain due to presence of PZ field.