Researchers in Germany, led by Dr. Neetesh Singh and Prof. Franz Kärtner, have developed a high-power tunable laser on silicon photonics. Using a large-mode-area (LMA) integrated waveguide amplifier, the study achieved nearly 2 Watts of output power. The study was published in the journal Light: Science & Applications.
The integrated large-mode area-based amplifier amplifies a tunable seed source to a few watts level. In this scenario, the seed and the pump are fully integrated together with the amplifier on to a silicon photonics platform. The device is deployed on a satellite orbiting a planet in or outside the solar system and generates high-power light of around 1.9 μm to map out the chemical makeup of the planet's atmosphere. The inset shows a large mode region in the amplifier where the mode is 10s of μm2, which allows large energy extraction from the silicon photonics-based LMA amplifier. Image Credit: Neetesh Singh et al.
In the modern world, systems that support ever-smaller components are getting smaller and smaller. Examples of these systems include high-speed data centers and small-scale satellites used for space exploration.
However, the ability of such systems to generate signal power has been seriously weakened by such miniaturization and high-density integration made possible by integrated photonics. Since their large volume allows for large energy storage capacity, high-power systems are traditionally thought to be found in meter-scale systems like fiber and solid-state systems.
The power generation capability of integrated photonics systems is still much lower than that of benchtop systems because optical energy storage capacity is much smaller in micron—to millimeter-scale systems, like those based on integrated photonics.
Silicon photonics-based lasers and amplifiers must produce high-power signals at a level equivalent to benchtop systems to replace bulky benchtop systems and enable the large-scale deployment of highly functional, mass-producible silicon photonics systems.
According to the researchers, such a device could revolutionize the field of photonics and enable the widespread use of integrated photonics devices in a variety of domains.
One possible use is the deployment of such a high-power tunable laser with a long wavelength window in small-scale satellites to detect and map out (using technologies like LIDAR) molecules that are necessary for life in space, such as carbon dioxide, water, and ammonia.
Compared to traditional fiber or solid state-based systems, the high-power tunable laser based on LMA silicon photonics will reduce the system size, weight, and cost by several orders of magnitude. This will enable several affordable space missions with previously unattainable highly enhanced capabilities.
This study supported the EU Horizon 2020 Framework Program and the German Deutsche Forschungsgemeinschaft (SP2111) program.
Journal Reference:
Singh, N., et al. (2025) Sub-2W tunable laser based on silicon photonics power amplifier. Light Science & Applications. doi.org/10.1038/s41377-024-01681-1.