Nonlinear semiconductor light sources

An apparatus, comprising:

• a substrate;
• a laser optical cavity being located over the substrate, the cavity having reflectors located at opposite ends thereof and a multi-layer structure located between the reflectors, the multi-layer structure comprising a first active semiconductor multi-layer and a second semiconductor multi-layer that is located laterally adjacent to the first active semiconductor multi-layer;
• and
• an electrode located over the substrate;
• and
• wherein the active semiconductor multi-layer comprises a sequence of quantum well structures that produce light of a lasing frequency in response to being electrically pumped by a pumping current from the electrode;
• and
• wherein the second semiconductor multi-layer comprises a sequence of quantum well structures configured both to resonantly absorb light of the lasing frequency via charge carrier excitations and to produce one of parametric light and harmonic light in response to absorbing light of the lasing frequency.