A breakthrough in laser technology has been achieved by miniaturizing an ultrafast mode-locked laser onto a nanophotonic chip using thin-film lithium niobate. This advancement paves the way for compact and efficient lasers with wide applications in imaging, sensing, and portable technologies.
New advances enable detailed execution in pocket-sized devices.
GPS – Free high-precision navigation, medical image processing, food safety inspection, etc.
Lasers are essential tools for observing, detecting, and measuring things in nature that cannot be seen with the naked eye. However, the ability to perform these tasks is often limited by the need to use expensive and bulky equipment.
Innovation in ultrafast laser technology
In a new cover story paper published in a magazine scienceIn , researcher Qiushi Guo demonstrates a new approach to creating high-performance, ultrafast lasers on nanophotonics chips. His research focuses on the miniaturization of mode-locked lasers. A mode-locked laser is a unique laser that emits a series of ultrashort coherent light pulses at femtosecond intervals, which is an astonishing one quadrillionth of a second.
Chip-scale ultrafast mode-locked laser based on nanophotonic lithium niobate.Credit: Alireza Marandi
Unraveling nature’s fastest timescales
Ultrafast mode-locked lasers are essential for unlocking the secrets of nature’s fastest timescales, such as the formation and breaking of molecular bonds during chemical reactions and the propagation of light through turbulent media. The high speed, pulse peak intensity, and wide spectral coverage of mode-locked lasers also enable numerous photonics technologies, such as optical atomic clocks, biological imaging, and computers that use light to calculate and process data. Ta.
Unfortunately, state-of-the-art mode-locked lasers are currently expensive, power-hungry benchtop systems that are limited to laboratory use.
Aiming for smaller and more efficient photonics
“Our goal is to revolutionize the field of ultrafast photonics by converting large lab-based systems into chip-sized systems that can be mass-produced and deployed in the field.” said Guo, a faculty member in the Photonics Initiative at the University’s Center for Advanced Science Research. Professor of Physics at New York University Graduate Center.
“In addition to miniaturization, we want to ensure that these ultrafast chip-sized lasers can provide satisfactory performance. requires sufficient pulse peak strength, preferably 1 watt or more.”
Challenge to miniaturization
However, achieving an effective mode-locked laser on a chip is not a simple process. Guo’s research leverages an emerging materials platform known as thin-film lithium niobate (TFLN). This material allows highly efficient shaping and precise control of laser pulses by applying external radio frequency electrical signals.
In their experiments, Guo’s team created a unique combination of III-V high laser gain. semiconductor TFLN’s efficient pulse shaping function nanoscale Using photonic waveguides, we demonstrate a laser capable of emitting high output peak power of 0.5 watts.
Future impacts and challenges
Beyond its compact size, the demonstrated mode-locked laser also exhibits many interesting properties that are unattainable with conventional lasers, leading to deep implications for future applications. For example, by adjusting the laser’s pump current, Guo was able to precisely tune the output pulse repetition frequency over a very wide range of 200 MHz. By leveraging the demonstrated strong reconfigurability of lasers, the research team hopes to realize chip-scale, frequency-stabilized comb light sources, which are essential for high-precision sensing.
Guo’s team still needs to take on additional challenges to achieve scalable, integrated, ultrafast photonic systems that can be translated for use in portable and handheld devices, but his lab has demonstrated Overcame a major obstacle in the construction.
Potential real-world applications
“This achievement paves the way to eventually use mobile phones to diagnose eye diseases and analyze food and the environment for E. coli and dangerous viruses,” Guo said. “This could also enable futuristic chip-scale atomic clocks that enable navigation even when GPS is compromised or unavailable.”
Learn more about this breakthrough advancement below.
Reference: “Ultrafast mode-locked lasers in nanophotonic lithium niobate” Qiushi Guo, Benjamin K. Gutierrez, Ryotosekine, Robert M. Gray, James A. Williams, Luis Ledezma, Luis Costa, Arkadev Roy, Selina Zhou, Mingchen Liu, and Alireza Marandi, November 9, 2023; science.
DOI: 10.1126/science.adj5438