Enlightra Prunes Lasers From WDM

The startup’s technology can create a hundred optical data carriers from a single laser, greatly reducing the cost and power of high-bandwidth optical links that use wavelength-division multiplexing.

Bryon Moyer

Startup Enlightra has developed a means of generating multiple optical carriers from a single continuous-wave laser source. The small-footprint photonic circuit can simplify optical data-center communications. High-bandwidth optical communication relies on wavelength-division multiplexing (WDM), in which multiple wavelengths—each acting as a carrier with its own signal—are mixed and transmitted together. Whereas a separate laser traditionally creates each carrier, Enlightra uses microresonators to spawn as many as 100 carriers from a single laser.

Because the carriers are related through their origin, variations caused by manufacturing or environmental changes track for them all, eliminating the need for large guard bands between carriers. Using two comb generators with interleaved lines, the company demonstrated a 55Tbps data rate over 75km of single-mode fiber—the highest rate achieved through a chip-scale generator.

Maxim Karpov and John Jost cofounded Enlightra in early 2021. Both have a research background, and they’ve funded the company largely on contract projects for European government and research agencies. Additional funds have come through association with various incubators; the company recently joined Y Combinator, which provided an additional $500,000 to reach a seed-funding round anticipated in 2024.

The most accessible application is inter- and intra-data-center communication—particularly as data centers move to an optical architecture employing a single laser source for multiple server racks. The technology can also serve long-haul optical communications, but that market is much slower to change owing to the entrenched infrastructure. The company’s present focus, therefore, is the data center. Having completed proofs of concept, its next goal is to develop a full laser transmitter for data centers, with a demonstrator scheduled for 2024 and full production expected in 2025 or 2026.