Si photonic crystal slow-light waveguides optimized through informatics technology

We modeled the photonic bands of SiO2-dadded Si lattice-shifted photonic crystal waveguides via machine learning and found a structure that generates low-dispersion slow light with a group index of approximately 20 in the full C-band at telecom wavelengths. The normalized delay-bandwidth product is as large as 0.45, which is close to the theoretical upper limit. The transition structure between this waveguide and a Si-channel waveguide was designed using an evolutional optimization, and a C-band average loss of 0.116 dB/transition was calculated. These results prove the possibility of further enhancing the versatility of slow light. (C) 2021 Optical Society of America

Automated summary

Machine learning was used to model the photonic bands of SiO2-dadded Si lattice-shifted photonic crystal waveguides, leading to the discovery of a structure that can generate low-dispersion slow light with a group index of approximately 20 in the full C-band at telecom wavelengths. The transition structure between this waveguide and a Si-channel waveguide was designed using an evolutional optimization, resulting in a C-band average loss of 0.116 dB/transition. These results suggest the potential for further enhancing the versatility of slow light.