PI-MOLL

Femtosecond mode-locked lasers (fs-MLLs) are key tools for generating optical frequency combs, enabling precision metrology, spectroscopy, LiDAR, terahertz generation, and microwave photonics. Yet current fs-MLLs rely on hand-assembled fiber oscillators, which are bulky, costly, and unsuited for volume applications. To address this bottleneck, fs-MLLs must be realized on photonic integrated circuits (PICs), combining performance with wafer-scale manufacturability. EPFL has recently demonstrated the first self-starting photonic integrated mode-locked laser (PI-MLL) that delivers femtosecond pulses with low noise and turnkey operation. The device merges two proven technologies: low-loss silicon nitride PICs with erbium ion implantation, yielding record-gain waveguide amplifiers, and semiconductor saturable absorbers (SESAMs), a mature solution for mode-locking. This approach enables 300-fs pulses at >1 GHz repetition rates with pulse energies up to 55 pJ, a pump threshold as low as 27 mW, and exceptional frequency comb stability. PI-MLLs can be packaged in standard butterfly modules and battery-powered, offering compact and robust solutions. The project PI-MOLL will advance this breakthrough to a packaged prototype (TRL 6) ready for customer testing. Technical objectives include photonic packaging, SESAM design, and integration. Application demonstrations will target terahertz time-domain spectroscopy for nondestructive testing and photonic analog-to-digital converters for microwave photonics. In parallel, commercialization activities - market analysis, IP build-up, trade fairs, and customer engagement—will be pursued with partners EDWATEC and MENLO Systems. By delivering the first wafer-scale manufactured chip-scale fs-MLL, PI-MOLL will overcome the limits of fiber-based lasers, unlock scalable and cost-effective solutions, and catalyze applications across metrology, imaging, LiDAR, and spectroscopy.