In a recent research paper in Science, Dr. Qiushi Guo and team present a groundbreaking method for creating high-performance ultrafast lasers on nanophotonic chips. These lasers, known as mode-lock lasers, emit extremely short and coherent light pulses in femtosecond intervals, one quadrillionth of a second. Mode-lock lasers are crucial for studying fast natural processes like chemical reactions and light propagation. However, current mode-lock lasers are expensive and limited to laboratory use. Guo’s research aims to revolutionize ultrafast photonics by developing chip-sized lasers that can be mass-produced and deployed in various applications.

The team uses thin-film lithium niobate (TFLN) material to create effective mode-lock lasers on a chip. TFLN allows for efficient shaping and precise control of laser pulses using an external radio frequency electrical signal. In their experiments, Guo’s team combined the high laser gain of III-V semiconductors with the pulse-shaping capability of TFLN nanoscale photonic waveguides. This resulted in a mode-lock laser emitting a high output peak power of 0.5 watts.

The demonstrated mode-lock laser offers a compact size and exhibits properties beyond conventional lasers. By adjusting the pump current, the research team could precisely tune the repetition frequencies of the laser pulses over a wide range. This reconfigurability opens up possibilities for chip-scale, frequency-stabilized comb sources essential for precision sensing. While there are still challenges to overcome in realizing scalable and integrated ultrafast photonic systems, this research breakthrough brings us closer to using chip-sized lasers in portable devices for medical diagnostics and environmental analysis applications.

In conclusion, Guo and team’s research significantly advances ultrafast photonics by developing chip-sized mode-lock lasers that deliver high performance. This breakthrough has the potential to revolutionize various industries and enable futuristic applications, including chip-scale atomic clocks for navigation in GPS-compromised environments.

References

• CUNY Advanced Science Research Center. (2023, November 9). Photonics team develops high-performance ultrafast lasers that fit on a fingertip. Phys.Org. https://phys.org/news/2023-11-photonics-team-high-performance-ultrafast-lasers.html
• Guo, Q., Gutierrez, B. K., Sekine, R., Gray, R. M., Williams, J. A., Ledezma, L., Costa, L., Roy, A., Zhou, S., Liu, M., & Marandi, A. (2023). Ultrafast mode-locked laser in nanophotonic lithium niobate. Science, 382(6671), 708–713. https://doi.org/10.1126/science.adj5438