Lasers developed at the 人妻少妇专区 offer a new path for on-chip frequency comb generators.
Light measurement devices called optical frequency combs have revolutionized metrology, spectroscopy, atomic clocks, and other applications. Yet challenges with developing frequency comb generators at a microchip scale have limited their use in everyday technologies such as handheld electronics.
In a published in Nature Communications, researchers at the describe new microcomb lasers they have developed that overcome previous limitations and feature a simple design that could open the door to a broad range of uses.
What are microcombs?
Optical frequency combs generate a spectrum of light consisting of multiple coherent beams, each tuned to a different frequency or color, in evenly spaced distances. The resulting shape resembles the teeth on a hair comb. In recent years, scientists have been working to create miniaturized versions of this technology, or microcombs, that can fit on small chips.
But while scientists have made progress in prototyping microcombs, they have had limited success producing viable versions that can be applied in practical devices. Obstacles include low power efficiency, limited controllability, slow mechanical responses, and the need for sophisticated system pre-configuration.
A simplified approach
A team of researchers led by , a professor in Rochester鈥檚 and at the , created a unique approach to solve these challenges in a single device.
According to Jingwei Ling, an electrical and computer engineering PhD student in Lin鈥檚 lab and the lead author of the paper, previous approaches usually rely on a single-wavelength laser injected into a nonlinear converter that can transfer the single wavelength into multiple wavelengths, forming the optical comb.
鈥淲e eliminated the single wavelength because that鈥檚 going to degrade the system鈥檚 efficiency,鈥� says Ling. 鈥淲e instead have all the comb itself being amplified in a feedback loop inside the system, so all the wavelengths get reflected and enhanced inside a single element.鈥�
The simplicity of the 鈥渁ll in one鈥� microcomb laser results in lower power demands, lower costs, high tunability, and a turnkey operation.
鈥淚t is easy to operate,鈥� says coauthor Zhengdong Gao, also an electrical and computer engineering PhD student in Lin鈥檚 lab. 鈥淭he previous methods make it hard to excite the comb, but with this method we only need to switch on the power source, and we can control the comb directly.鈥�
Hurdles remain for implementing these microcomb lasers, particularly with developing fabrication techniques to create such tiny components within the tolerances necessary for manufacturing. But the researchers are hopeful that their devices can be used for applications such as telecommunications systems and light detection and ranging (LiDAR) for autonomous vehicles.
The Defense Advanced Research Projects Agency and the National Science Foundation supported this research.
