A lab accident led engineers to build a chip that fires a rainbow of powerful lasers, and could help data centers better manage massive amounts of data. artificial intelligence (i) History.
The new photonics chip contains an industrial-grade laser source combined with a precisely engineered optical circuit that shapes and stabilizes the light before splitting it into multiple, evenly spaced colors.
Uses of lidar Laser Pulses measure distance based on the time it takes to reach and bounce back from an object. While trying to produce more powerful lasers capable of capturing detailed data from a distance, the team noticed that the chip was splitting the light into multiple colors.
What is frequency comb?
A frequency comb is a type of laser light consisting of multiple colors or frequencies evenly spaced across Optical spectrum. When plotted on a spectrogram, these frequencies appear as spines that resemble the teeth of a comb.
The peak of each “tooth” represents a fixed, precisely defined wavelength that can carry information independently of the others. Because the wavelengths are restricted in both frequency and phase—meaning that their peaks remain perfectly consistent—they do not interfere with each other. This allows multiple data streams to travel in parallel over a single optical channel, such as a fiber optic cable.
After stumbling upon the effect by accident, scientists designed a way to reproduce it intentionally and controllably. They also packed the technology into a silicon chip where light travels through waveguides just micrometers wide; One micrometer (1 µm) is one thousandth of a millimeter (0.0001 cm), or approximately one-hundredth of the width of a human hair.
The team published their findings on October 7 in the journal Nature photonics. This breakthrough is especially important now that artificial intelligence is putting more and more Resource pressure on data center infrastructureThe researchers said.
“Data centers have created a tremendous demand for powerful, efficient light sources that contain many wavelengths,” study co-author Andres Gil Molina“We’ve got a lot of data going on,” said principal engineer at Xscape Photonics and former researcher at Columbia Engineering statement.
“The technology we’ve developed takes an extremely powerful laser and turns it into dozens of clean, high-power channels on a chip. This means you can replace racks of individual lasers with a single compact device, reducing cost, saving space and opening the door to much faster and more energy-efficient systems.”
Rainbow on a chip
To create a frequency comb on a chip, researchers needed to find a high-powered laser that could be squeezed into a compact optical circuit. They eventually settled on a multi-mode laser diode, which is widely used in medical devices and laser cutting tools.
Multi-mode laser diodes can produce powerful beams of laser light, but the beam is “chaotic,” meaning researchers need to know how to optimize and stabilize the light to make it workable, the researchers said in the study.
They achieved this using a technique called self-injection locking, which involves embedding resonators into the chip that feed a small portion of the light back to the laser. This filters and stabilizes the light, resulting in a very powerful and stable beam.
Once stabilized, the chip splits the laser beam into a multi-color frequency comb. The result is a small but effective optical device that combines the power of an industrial laser with the precision needed for data transmission and sensing applications, the scientists added.
Beyond data centers, the new chip could enable portable spectrometers, ultra-precise optical clocks, Embedded quantum devices And even Advanced lidar systems.
“It’s about bringing light sources used in laboratories into real-world devices,” Gil Molina said. “If you can make it strong, efficient and small enough, you can put it almost anywhere.”