A monolithic integrated optical transmitter comprising (a) an optical source including two output optical paths and (b) a modulator section that includes an interferometric optical signal combiner is described. Each of the two output optical paths of the optical source includes a reflector. The optical source is configured to output a first light beam through the first optical path and a second light beam through the second optical path. The optical transmitter is capable of generating advanced modulation format signals based on amplitude and phase modulation.