Wavelength division multiplexers are fundamental to the functioning and performance of integrated photonic circuits, with applications ranging from optical interconnects to sensing and quantum technologies. In fiber-optic communications, wavelength-division multiplexing (WDM) is a technology which multiplexes a number of optical carrier signals onto a single optical fiber by using different wavelengths (i. Current solutions are limited by trade-offs between channel spacing, crosstalk, insertion. In ultra-high-density environments, like hyperscale data centers, making the most of every square inch is a must. WDM lets you increase capacity and lower latency within your existing footprint.