One-dimensional simulation on quantum-well laser diodes in steady-state had been studied in this work. The electrical behaviors are obtained by solving Poisson's equation and current continuity equations for electrons and holes using a self-consistent method. Band parameters are added in the continuity equations for compositional change in each layer. Different forms of band parameters are used in quantum well regime. The recombination model are revised in the quantum well regime. After the electron and hole profiles are obtained, the peak gain in the quantum well regime are then calculated. The model for the optical matrix element used in this study includes intraband relaxation but without band mixing effects. Wave equation is solved to obtain the optical field intensity and the optical confinement factor. Modal gain and total loss are then calculated. This procedure proceeds until the modal gain is greater than the loss. We use this method to simulate both graded-index separate-confinement heterostructure (GRIN-SCH) quantum-well laser and separate-confinement heterostructure (SCH) quantum- well laser for AlGaAs-GaAs system. Results show that the carriers are well-confined in GRIN-SCH laser, thus less recombination current density present outside the quantum well regime in GRIN-SCH than in SCH. The optical confinement factor depends strongly on the waveguide structures. It may be better confined in GRIN-SCH than in SCH for a set of layer thickness and poorly confined for another set of layer thickness. Thus, the threshold current density depends on the structure. The calculated threshold current density is slightly lower than the experimental result.

Date Published: 23 October 1992
PDF: 12 pages
Proc. SPIE 1813, Optoelectronic Component Technologies, (23 October 1992); doi: 10.1117/12.131256

Published in SPIE Proceedings Vol. 1813:
Optoelectronic Component Technologies
GouChung Chi; Chi-Shain Hong, Editor(s)