Analysis of the phase-locking dynamics of a III-V-on-silicon ring mode-locked laser

We present the detailed phase-locking analysis of a telecom hybrid III-V-on-silicon passively mode-locked laser with a ring cavity and quantum wells as active region. We use a stepped-heterodyne measurement to quantify the modal phase chirp and reconstruct the pulse envelop. With this technique we are able to identify regimes of transform-limited operation and we assess the degradation of the phase-locking when saturable absorber bias voltage is changed.