Compact Generator of an Optical Frequency Comb Based on Distributed-Feedback Laser Diode and High-Q Optical Microcavity

Abstract—Optical frequency combs are a unique tool for fundamental metrology and spectroscopy; they are also used in various applications. High-Q microcavities are promising for generating coherent frequency combs. An approach based on the pulling effect, which is well-known in radiophysics, is proposed. The use of this effect makes it possible to develop a compact, commercially available source of an optical comb and microwave radiation based on a compact distributed-feedback laser diode with a low output power of 6 mW and a microcavity based on magnesium fluoride with a Q factor of 10⁹. Different generation modes of optical frequency combs, corresponding to different numbers of generated solitons at a pump power of 6 mW and a wavelength of 1550 nm, as well as spectrally pure microwave radiation at a frequency of 12.94 GHz, are demonstrated.