An ultra-broadband photonic integrated circuit platform that combines at least two types of waveguides that each transmit in different, but overlapping, spectral bands on a single chip. By combining the multiple waveguides, the bandwidth of the platform can be extended beyond the bandwidth of either waveguide alone. In an exemplary embodiment, an ultra-broadband photonic integrated circuit includes a nitride-on-insulator (NOI) waveguide configured to transmit optical beams in a first spectral band and a silicon-on-nitride-on-insulator (SONOI) waveguide configured to transmit optical beams in a second band, where the same material serves as the core material in the NOI waveguide and as the cladding material in the SONOI waveguide. In some embodiments, light-emitting devices are bonded to an upper surface of the waveguides. In some embodiments, the circuit includes beam-combining elements so that a single beam combining all of the input wavelengths is output from the circuit.