Heterogeneously integrated DFB and DBR membrane lasers for high speed direct modulation

We discuss how heterogeneously integrated membrane laser diodes can be designed to give very high direct modulation bandwidths. Their membrane structure allows high optical confinement as well as low parasitic capacitance. Moreover, one can make use of the very low loss of SOI waveguides and of very efficient tapers to couple the membrane lasers to well-defined, low-loss external cavities and one can thus exploit the external cavity resonance in the modulation response.