Researchers from Chalms University of Technology in Sweden have successfully improved the efficiency of optical combs to become a high-performance laser

Researchers from Chalms University of Technology in Sweden have successfully improved the efficiency of optical microcombiners, making them a high-performance laser. This breakthrough will have a wide impact in fields such as space science and healthcare.

The two rings in the figure are micro resonators, which play a crucial role in the implementation of efficient micro combs.

The importance of micro comb technology
The optical micro comb technology has significant scientific and technological application potential. It can be used for high-precision frequency measurement and is considered one of the most disruptive technologies since the birth of lasers. In short, a micro comb is like a ruler made of light, which can accurately measure the frequency of light.

Its working principle is based on the laser sending photons, which circulate in the micro resonator, causing light to be divided into multiple precise frequencies. These frequencies can be accurately positioned against each other, just like scales on a ruler. Therefore, a micro comb can create a light source containing hundreds or even thousands of frequencies, similar to a laser beam emitted uniformly.

Due to the fact that almost all optical measurements are related to the frequency of light, micro comb technology has a wide range of applications, from instruments used to calibrate and measure light year distance signals in space science to tracking health status through air analysis in healthcare.

Key breakthroughs in solving efficiency issues
However, the previous micro comb technology had a fundamental problem, which was its low efficiency. The energy conversion efficiency between light and micro combs is not high, resulting in only a small portion of power available in the laser beam.

Researchers have made breakthrough progress on this issue. By using two micro resonators, they successfully increased the power of the micro comb laser beam, increasing the efficiency from about 1% to over 50%. This method utilizes the interaction between two micro resonators, where one resonator couples light from the laser with the other resonator, similar to impedance matching in electronic circuits.

Prospects and Applications
The method described in this study has opened up a new field for the application of high-performance lasers and has been patented. Researchers have also established a start-up company, Iloomina AB, to push this technology to a wider market.

The new micro combs have enormous transformative potential as they enable high-performance laser technology to be used in more markets. For example, frequency combs can be used for autonomous LiDAR modules, GPS satellites, and environmental sensing drones, as well as supporting bandwidth intensive artificial intelligence applications in data centers. This breakthrough will accelerate the adoption of high-performance laser technology in various fields, including healthcare and space science.

Source: China Optical Journal Network