MicroLEDs, measuring no wider than a human hair—approximately 100 micrometers in diameter—are emerging as a potential substitute for lasers in applications such as short-distance data transfer within server racks and the development of next-generation displays. Recent research conducted by the University of California, Santa Barbara (UCSB) presents a significant advancement in microLED technology, enhancing both the efficiency and directionality of the emitted light.
A study published in Optica Express outlines a novel microLED design that addresses critical limitations found in previous models. Under the guidance of doctoral student Roark Chao, the research team achieved an impressive 20% increase in optical output through air-side emission, over 130% higher output through the substrate side, and a reduction of approximately 30% in beam divergence compared to standard microLEDs. This was made possible by laterally enclosing the emitting region with distributed Bragg reflectors.
Chao noted that “we’re talking about devices that are literally the size of a hair follicle. If you can engineer how the light comes out, those microLEDs can start to replace lasers in short-distance data communication.” This sentiment underscores the transformative potential of microLEDs in advancing data communication technologies.
The research builds upon UCSB’s strong foundation in gallium nitride research and optoelectronics. Chao is co-advised by Steven P. DenBaars and Jon A. Schuller, both of whom are co-authors of the study. Significantly, the team also included Shuji Nakamura, a Nobel laureate celebrated for his groundbreaking work on blue LEDs, which have revolutionised lighting and display technologies worldwide.
In addition to enhanced beam control, the redesigned microLEDs demonstrate significantly improved efficiency. The researchers observed around 35% higher electrical efficiency and approximately 46% higher wall-plug efficiency, indicating that these devices convert a greater proportion of input power into usable light when compared to traditional microLED designs.
This advancement positions microLEDs as a promising alternative to lasers across various applications. Their compact size and enhanced performance make them particularly well-suited for high-density data communication and the next generation of 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.