3D printed multimode-splitters for photonic interconnects

Abstract

Photonic waveguides are promising candidates for implementing parallel, ultra-fast and ultra-low latency interconnects. Such interconnects are an important technological asset for example for next generation optical routing, on and intra-chip optical communication, and for parallel photonic neural networks. We have recently demonstrated dense optical integration of multi-mode optical interconnects based on 3D additive manufacturing using two-photon-polymerization. The basis of such interconnects are 3D optical splitters, and here we characterize their performance against their splitting ratio, geometry, and conditions of the direct laser writing. Optical losses and splitting uniformity of 1 to 4, 1 to 9 and 1 to 16 splitters are evaluated at 632 nm. We find that, both, the uniformity of splitting ratios as well as the overall losses depend on the separation between the output waveguides as well as on the hatching distance (surface quality) of the 3D printing process.