Nature Photonics | New Comb Laser Assists Stable and Efficient Generation of Multi wavelength Signals

Recently, researchers have developed a comb laser with higher stability and efficiency. The use of synthetic reflection self injection locking micro comb design enables the laser to achieve stability and increase conversion efficiency by more than 15 times. This efficient, stable, and easy to manufacture design is expected to make rapid progress in fields such as portable sensors, autonomous navigation, and large bandwidth data processing.

In a new paper published in Nature Photonics, researchers reported improvements in the stable generation of multi wavelength signals using micro integrated comb laser systems. This study is a collaboration between the German Center for Electronic Synchrotron Radiation (DESY Hamburg) and a Swiss startup called Enlightra, which focuses on developing efficient multi wavelength lasers for high-capacity data transmission and optical computing. The author states that light sources are a key technology that drives optical communication to reach the data rate required by artificial intelligence.

This paper titled "Synthetic reflection self injection locked microcombs" showcases a special design. By introducing a customized nanostructure into the ring resonator in a micro comb system, the integrated comb laser can emit laser radiation in a stable and efficient manner. This novel design can improve the performance of comb lasers, enabling them to play a better role in fields such as optical communication and optical computing.

This study demonstrates a microcavity resonator with programmable synthetic reflection, providing customized injection feedback for driving lasers. This synthetic reflection enables them to achieve stable and definite working states of self injection locking micro combs. This is in stark contrast to the traditional self injection locking based on random defect scattering.

Dr. John Jost, one of the authors, said, "This is stability achieved through design. In addition to stability, we have also increased conversion efficiency by more than 15 times."

As part of the research, the author conducted various tests using different nanostructured ring resonators and docked semiconductor laser diodes with photonic chips. The resonator is designed using a photonic crystal micro ring structure based on a silicon nitride platform and prepared through ultraviolet lithography technology. The study was only demonstrated in the C-band, but the researchers stated that it performed equally well in all communication bands.

The comb laser proposed by this research institute can be widely produced and integrated with other photonic integrated circuits. Therefore, it can support fast optical input/output units or optical programmable gate arrays, which is of great significance for data intensive applications such as generative artificial intelligence and novel non integrated computer and memory architectures.

According to researchers, this is the first time that back reflection technology has been used to achieve stable and efficient generation of laser combs. With this stable, efficient, and easy to manufacture new design, laser micro combs are expected to make rapid progress in applications such as portable sensors, autonomous navigation, or extremely wide bandwidth data processing.

Source: Sohu