CEA-Leti, a French government-funded technological research organization, is set to launch a multi-year initiative aimed at exploring how microLEDs can be used to support ultra-fast data transfers.

Set to kickstart in January 2026, the three-year project will leverage the group’s nearly two-decade experience in microLED R&D on a lab-to-fab initiative aimed at determining if microLEDs can be a more efficient alternative to copper- or laser-based data technologies.

The project looks to build on Mosaic – a prototype interconnect system developed by Microsoft that uses directly modulated microLEDs capable of maintaining high network speeds across longer distances while using far less power.

CEA-Leti researchers will lead the Multilateral MicroLED Data Link Program, an attempt to create a technical roadmap aimed at creating a microLED technology as a “compelling alternative” to copper and laser-based data systems.

“MicroLED represents a true paradigm shift for short-range optical, point-to-point data interconnects,” CEA-Leti CEO Sébastien Dauvé explained. “It delivers extremely high data-density transfer rates with far better energy efficiency than current technologies. Unlike silicon photonics or VCSEL (vertical-cavity surface-emitting lasers), microLED is scalable for massive parallel communication.”

“By combining the complementary expertise of our program members, we aim to break through the interconnect power and density bottlenecks that limit next-generation computing,” Dauvé added.

All the little lights

Microsoft’s Mosaic paper saw it employ microLEDs, which operate at lower speeds and improved power efficiency by eliminating the need for complex electronics and reducing optical power requirements. The technology also enables reach to be greatly extended, reaching distances of up to 50 meters, compared to just two meters.

Due to their small size, microLEDs have the potential to be modulated at several gigabits per second and are placed in large groups, or arrays.

The tech is typically employed in smartwatches. There, more than half a million microLEDs might feature, with their simple structure and temperature insensitivity making them more reliable than lasers.

In addition, their size makes them even more ideal to aid growing data densities. Microsoft engineers suggested a potential 800 Gb/s Mosaic link would require a 20 millimeters by 20 millimeters (20x20) microLED array – meaning it would fit on a die less than one millimeter by one millimeter.

This technology is also fully compatible with today’s pluggable transceivers’ form factors and is as protocol-agnostic as it simply relays bits from one endpoint to another.

Microsoft engineers are already looking to potentially “productize” Mosaic and scale it for mass production.