Improved high-frequency response of InGaAsP double-channel buried-heterostructure lasers

Several modifications of the InGaAsP double-channel buried-heterostructure laser diode are described with reduced parasitic capacitances in order to improve the modulation speed of the laser chip. The parasitic capacitances of the various devices are measured and the data are described in terms of an improved microwave circuit model for BH lasers. A modulation bandwidth of more than 3 GHz is experimentally obtained by means of proton isolation of the laser chip outside the active region.