Modelling and numerical simulation of the optical intensity distribution in double-heterostructure semiconductor lasers

摘要

The optical intensity distribution is theoretically studied in a double-heterostructure (DH) Al_xGa_(l-x)As-GaAs material system using PICS3D (Photonic Integrated Circuit Simulator in 3D) software simulation. The electrical and optical equations to describe the behaviour of semiconductor lasers are reviewed. To investigate the optical and carrier confinement in basic DH, the index x of AlAs mole fraction is varied. From computational results and technological considerations, index x 0.35 is chosen for a dielectric slab waveguide. In order to accomplish optical and electrical confinement in the lateral direction, oxide-stripe and ridge waveguide geometry is treated. The light versus current characteristics (L-I), electron concentration profiles, optical intensity distribution, as well as current flow are evaluated. Finally, it follows from the computed characteristics that optical and carrier confinement in transverse and lateral directions is accomplished for ridge-waveguide geometry with a ridge height of 540 nm.