Phys.org  July 27, 2023 The formation of a broadband optical frequency comb relies on careful engineering of the group velocity dispersion (GVD) of the waveguide, which is challenging for platforms where the GVD is mainly determined by the material. An international team of researchers (USA – UC Santa Barbara, Egypt) has generated a 60 GHz quantum-dot (QD) mode-locked laser in which both the amplitude-modulated (AM) and the frequency-modulated (FM) comb could be generated independently. The high four-wave-modulated (FWM) efficiency of –5 dB allowed the QD laser to generate FM comb efficiently. They demonstrated that the Kerr nonlinearity could be practically engineered to […]