A 36 × 240 Gbps hybrid mode/wavelength division multiplexing transmitter using lithium niobate on insulator

In the era of big data and artificial intelligence, the explosive growth of data capacity has driven unprecedented demands for high-capacity and high-speed optical communication systems. The traditional single-mode and single-wavelength transmission technologies can no longer meet the requirements of massive data transmission, thereby continuously driving the industry to explore more efficient multiplexing schemes. Here, a hybrid 6-mode × 6-wavelength division multiplexing transmitter based on lithium niobate-on-insulator (LNOI) is proposed as a groundbreaking solution for next-generation optical communication. The transmitter innovatively combines six different waveguide modes (TE₀–TE₅ modes) with six wavelengths spaced 3.2 nm apart, enabling the dense multiplexing of 36 independent channels within a compact optical bandwidth and achieving a capacity of 36 × 240 Gbps. The 3.2 nm channel spacing (approximately 400 GHz at 1550 nm) complies with the ITU-T grid standards, ensuring compatibility with existing optical network infrastructures. Meanwhile, the mode division multiplexing component utilizes multi-mode waveguides to fully leverage the spatial degrees of freedom in optical transmission, thereby significantly enhancing the spectral efficiency of the system compared to traditional single-mode solutions. This hybrid mode/wavelength division multiplexing architecture exhibits excellent applicability in next-generation data center interconnections and long-haul optical transmission networks.