The development of compact coherent sources has been strongly triggered by the emergence of optical telecommunications in the 70’s. Continuous wave single mode lasers or frequency comb sources are unavoidable modern photonic tools for a wide variety of applicative domains ranging from trace gas detection to optical clocks. A trend consists in harvesting the know-how acquired in the near infrared band to spread it to surrounding regions of the optical spectrum. The COMBO project is part of this process addressing the blue range of the spectrum between 405 and 480 nm.

Two main breakthroughs are targeted: the first demonstration of a Kerr frequency comb in the blue range using a high-Q resonator; and an electrically-pumped sub-kHz linewidth single mode Fabry-Perot (SFP) laser based on resonant optical feedback. Combining these two contributions should yield to the demonstration of a compact blue Kerr frequency comb generator.

Combo is a young researcher projet supported by the French National Research Agency (ANR). The three-year project started officially on April 1, 2019 aims to demonstrate cutting edge coherent sources in the blue light range.