Integrated optical comb generation for coherent communications using injection locked semiconductor lasers

Slotted Fabry-Perot (SFP) semiconductor laser diodes provide single mode operation [1], which is useful in various telecommunications applications. Under optical injection locking these lasers can be used in the production of single mode coherent combs. These combs have potential application in Coherent Wavelength Division Multiplexing (CoWDM) [2]. They are also an ideal candidate for Photonic Integrated Circuits (PIC's) as they satisfy the requirement of low power consumption. Another major advantage of these lasers is that they can be fabricated using a single epitaxial growth step. This means that fabrication costs can be kept to a minimum and that the fabrication process can be easily transferred to existing foundry processes. Coherent communication techniques can be used to increase the ISD but requires coherence between the separate channels involved. One particular modulation scheme, CoWDM, is focused on in this work [2].