Generation of Soliton Microcomb at O-band in Chip Scale Microresonators via Pump Modulation

We demonstrate the generation of optical soliton microcombs at O-band in chip-scale and high-Q silicon nitride (Si 3 N 4 ) microresonators, which is driven by a phase modulated single frequency pumping laser. The modulation induced pumping sideband serves to maintain thermal equilibrium in the cavity and restore the soliton accessibility. The majority of the soliton existence range is extended by a factor of 6.