Technologies for generating a broadband optical output include a plurality of narrowband optical sources formed in a silicon substrate to generate a narrowband optical output, a plurality of input optical waveguides to route the narrowband optical output, an optical multiplexer formed in the silicon substrate to reflect the routed narrowband optical output, and an output optical waveguide to collect the reflected narrowband optical output to generate the broadband optical output. The output optical waveguide may route the broadband optical output to an output of the photonic integrated circuit.