Broadest microcomb spectral span on record

Xu Yi, assistant professor of electrical and computer engineering at the University of Virginia, collaborated with Yun-Feng Xiao s group from Peking University and researchers at Caltech to achieve the broadest recorded spectral span in a microcomb.


Their peer-reviewed paper, "Chaos-assisted two-octave-spanning microcombs," was published May 11, 2020, in Nature Communications, a multidisciplinary journal dedicated to publishing high-quality research in all areas of the biological, health, physical, chemical and Earth sciences.

The team applied chaos theory to a specific type of photonic device called a microresonator-based frequency comb, or microcomb. The microcomb efficiently converts photons from single to multiple wavelengths. The researchers demonstrated the broadest (i.e., most colorful) microcomb spectral span ever recorded. As photons accumulate and their motion intensifies, the frequency comb generates light in the ultraviolet to infrared spectrum.

"It s like turning a monochrome magic lantern into a technicolor film projector," Yi said. The broad spectrum of light generated from the photons increases its usefulness in spectroscopy, optical clocks and astronomy calibration to search for exoplanets.

The microcomb works by connecting two interdependent elements: a microresonator, which is a ring-shaped micrometer-scale structure that envelopes the photons and generates the frequency comb, and an output bus-waveguide. The waveguide regulates the light emission: only matched speed light can exit from the resonator to the waveguide. As Xiao explained, "It s similar to finding an exit ramp from a highway; no matter how fast you drive, the exit always has a speed limit."

The research team figured out a smart way to help more photons catch their exit. Their solution is to deform the microresonator in a way that creates chaotic light motion inside the ring. "This chaotic motion scrambles the speed of light at all available wavelengths," said co-author and Peking University research team member Hao-Jing Chen. When the speed in the resonator matches that of the output bus-waveguide at a specific moment, the light will exit the resonator and flow through the waveguide.

The team s adoption of chaos theory is an outgrowth of their previous study on chaos-assisted broadband momentum transformation in deformed microcavity, which was published in Science in 2017 (Science 358, 344-347).

This research builds on UVA Engineering s strengths in photonics. The Charles L. Brown Department of Electrical and Computer Engineering has a solid foundation in semiconductor materials and device physics that extends to advanced optoelectronic devices. Yi s microphotonics lab conducts research on high-quality integrated photonic resonators, with a dual focus on microresonator-based optical frequency combs and continuous-variable-based photonic quantum computing.

"The introduction of chaos and cavity deformation not only provides a new mechanism, but also an additional degree of freedom in designing photonic devices," Yi said. "This could accelerate optics and photonics research in quantum computing and other applications that are vital to future economic growth and sustainability."

Materials provided by . Original written by Karen Walker. Note: Content may be edited for style and length.

University of Virginia School of Engineering and Applied Science. "Broadest microcomb spectral span on record: With greater freedom to design photonic devices, researchers can accelerate optics and photonics research." ScienceDaily. ScienceDaily, 21 May 2020. .

University of Virginia School of Engineering and Applied Science. "Broadest microcomb spectral span on record: With greater freedom to design photonic devices, researchers can accelerate optics and photonics research." ScienceDaily. (accessed May 23, 2020).



Sep. 9, 2019 — Scientists have announced that they achieved the highest magnetic field strength ever recorded for an accelerator steering magnet, setting a world record of 14.1 teslas, with the magnet cooled to 4.5 ...

Sep. 19, 2018 — Newly identified bridge forms could enable significantly longer bridge spans to be achieved in the future, potentially making a crossing over the Strait of Gibraltar, from the Iberian Peninsula to ...

June 22, 2017 — Techniques to acquire spectral data have been static for a long time - until now. Exciting and novel spectral video technologies are emerging, allowing us to extract increasingly dynamic knowledge ...

Sep. 28, 2016 — Researchers have achieved unprecedented transmission capacity and spectral efficiency in an optical communications field trial with a new modulation technique. The breakthrough research could extend ...
News Topics :
Optical frequency combs are laser sources whose spectrum consists of a series of discrete, equally spaced frequency lines that can be used for precise measurements. In the last two decades,...
In our information society, the synthesis, distribution, and processing of radio and microwave signals are ubiquitous in wireless networks, telecommunications, and radars. The current tendency is to use carriers in...
A team of physicists at the University of Bristol has developed the first integrated photon source with the potential to deliver large scale quantum photonics. advertisement The development of quantum technologies...
Close Ultrashort optical pulses are becoming more and more relevant in a number of applications including distance measurement, molecular fingerprinting and ultrafast sampling. Many of these applications rely not only...
A new integrated photonics platform that can store light and electrically control its frequency or color in an integrated circuit. Credit Loncar Lab/HarvardSEAS A new integrated photonics platform that can...