Photonic Lanterns, 3-D Waveguides, Multiplane Light Conversion, and Other Components That Enable Space-Division Multiplexing

Four-mode multiplexing and manipulation technologies are reviewed in the context of space-division (SDM) optical communication systems. These multiplane light conversion (MPLC), fused fiber devices, such as photonic lanterns tapered bundles, 3-D waveguides fabricated using ultrafast laser inscription, free-space imaging Each device has its unique strengths use cases. MPLC can create very complex transformations between two arbitrary sets spatial modes leverages mature gray-scale lithographic techniques. Photonic bundles all-fiber devices that convert beams on single-mode inputs into modes. The construction leads to low losses high-power handling. inscribed a glass block ultrashort lasers arbitrarily route 3-D. Finally, systems lenses also relay many multicore multimode through single device, thin film filter or an isolator. four have enabled hero transmission experiments multimode, multicore, fiber.