Eurekalert February 11, 2019
Electrically-driven, photonic chip-based microcombs are inhibited by the required high threshold power and the frequency agility of the laser for soliton initiation. An international team of researchers (Switzerland, Russia) has built an integrated soliton microcomb operating at a repetition rate of 88 GHz using a chip-scale indium phosphide laser diode and the silicon nitride microresonator. At only 1 cm in size, the device is the smallest of its kind to-date. A small portion of the laser light is reflected back to the laser due to intrinsic scattering from the microresonator. This direct feedback helps to both stabilize the laser and generate the soliton comb. This shows that both resonator and laser can be integrated on a single chip offering a unique improvement over past technology…read more. Open Access TECHNICAL ARTICLE
A PHOTOGRAPH OF THE MICRORESONATOR-FREQUENCY COMB SYSTEM. CREDIT: ARSLAN RAJA/EPFL