Vertically compact 15 GHz GaAs/AlGaAs multiple quantum well laser grown by molecular beam epitaxy

A GaAs/AlxGa1−xAs multiple quantum well laser with an electrical modulation bandwidth exceeding 15 GHz has been fabricated. Optimised design of the waveguide, including development of high Al mole fraction (x = 0.8) cladding layers, together with a coplanar electrode geometry, has resulted in a vertically compact laser structure suitable for integration.