Hair-Width LEDs Poised to Replace Lasers in Data Communication

LEDs no wider than a human hair—roughly 100 micrometers in diameter—are rapidly advancing as a potential replacement for lasers in applications like short-distance data transfer within server racks and powering next-generation displays. New research from UC Santa Barbara (UCSB) demonstrates a practical path forward for these microLEDs, improving both their efficiency and the directionality of the emitted light.

Breakthrough in MicroLED Design

A study published in Optica Express details a novel microLED design that addresses key limitations of previous iterations. Researchers, led by doctoral student Roark Chao, achieved roughly 20% higher optical output through air-side emission, over 130% higher output through the substrate side, and approximately 30% reduced beam divergence compared to conventional microLEDs. This was accomplished by laterally enclosing the emitting region with distributed Bragg reflectors.

The Science Behind the Advancement

“We’re talking about devices that are literally the size of a hair follicle,” explained Chao, an electrical engineering student at UCSB. “If you can engineer how the light comes out, those microLEDs can start to replace lasers in short-distance data communication.”

The research builds upon UCSB’s established expertise in gallium nitride research and optoelectronics. Chao is co-advised by Steven P. DenBaars and Jon A. Schuller, both co-authors of the study. Notably, the research team as well included Shuji Nakamura, a Nobel laureate recognized for his pioneering work on blue LEDs, which revolutionized global lighting and display technologies.

Enhanced Efficiency and Performance

Beyond improved beam control, the redesigned microLEDs exhibit significantly higher efficiency. The team observed roughly 35% higher electrical efficiency and about 46% higher wall-plug efficiency—meaning the devices convert a greater percentage of input power into usable light compared to traditional microLED designs.

Implications for the Future

This advancement paves the way for microLEDs to become a viable alternative to lasers in various applications. Their small size and improved performance develop them particularly well-suited for high-density data communication and next-generation display technologies. The research was conducted in the laboratories of the DenBaars/Nakamura and Schuller groups, focusing on gallium nitride materials growth and nanoscale photonics.