Coupled multi quantum well 650-nm emitting GaInP laser diodes

摘要

650nm emitting lasers are required for a number of applications including DVD. A combination of requirements, such as narrow far-field divergence, low temperature dependence of threshold current and low absolute operating current make device design difficult. We have adopted the approach of using coupled multiple quantum wells to minimise quasi-Fermi level separation and hence carrier leakage while using a simple low optical confinement structure, with small refractive index step between waveguide core and cladding, to optimise far-field divergence. The samples studied consist of either 3, 4 or 5 coupled quantum wells set in a waveguide core of (Al_xGa_(1-x))_(0.5)In_(0.5)P (0.52