Inverse-Designed Photonic Jumpers With Ultracompact Size and Ultralow Loss

Photonic integrated circuits are an ideal platform for chip-scale computation and communication. A complex photonic network usually requires components to direct light from one waveguide to another that is parallel to the former with an arbitrary separation d. Traditionally, this is achieved with S-shaped waveguide bends, which either occupy a large footprint or suffer from large insertion loss. To reduce the footprint and maintain ultralow insertion loss, here we propose and experimentally demonstrate inverse-designed photonic jumpers on a silicon-on-insulator platform. These photonic jumpers have ultracompact sizes by achieving the expected function within a footprint of d × 2.5 μm, while the simulated and measured insertion loss for the fundamental transverse-electric mode maintains below 0.14 and 0.30 dB, respectively, in the wavelength range of 1.50-1.60 μm. Therefore, these photonic jumpers can be used in large-scale photonic integrated circuits as a standard module to significantly enhance the integration density.