Highly-Efficient Seeded Frequency Comb Generation on a Chip

Generating new colors (frequency components) of light through nonlinear optical phenomena is one of the key drivers of modern optical technology.

The spectrally diverse coherent light, widely known as an optical frequency comb, can be produced through a nonlinear process.

The optical frequency comb enables energy-efficient optical communication, precision spectroscopy, and optical atomic clock.

However, the frequency comb sources currently rely on bulky and power-hungry laser systems hampering their deployment outside the laboratory environment. There are great demands in lowering the size, weight, and power (SWaP) of such broadband light sources.

Despite the significant progress in the miniaturization of comb systems and microcomb technologies. it is still a huge challenge to drive a broadband (larger than an octave) comb with microwave repetition rate using on-chip pump sources due to the limited performance of on-chip lasers.

The COMBCHIP project aims to develop an ultra-efficient comb generator by combining the highly nonlinear AlGaAs waveguide and a newly developed seeded pumping scheme.

The developed comb sources feature an octave-spanning bandwidth, microwave repetition rate, and ultra-low operation power, enabling chip-scale comb systems in emerging applications such as atomic optical clocks in satellites and mid-infrared spectroscopy.