Wideband Slow Light in a Line-defect Annular Photonic-crystal Waveguide

  • Kuang, Feng (College of Electronic and Optical Engineering & College of Microelectronics, Nanjing University of Posts and Telecommunications (NJUPT)) ;
  • Li, Feng (New Energy Technology Engineering Laboratory of Jiangsu Province & School of Science, Nanjing University of Posts and Telecommunications (NJUPT)) ;
  • Yang, Zhihong (New Energy Technology Engineering Laboratory of Jiangsu Province & School of Science, Nanjing University of Posts and Telecommunications (NJUPT)) ;
  • Wu, Hong (New Energy Technology Engineering Laboratory of Jiangsu Province & School of Science, Nanjing University of Posts and Telecommunications (NJUPT))
  • Received : 2019.05.02
  • Accepted : 2019.07.27
  • Published : 2019.10.25


In this theoretical study, a line-defect photonic-crystal waveguide hosted in an annular photonic crystal was demonstrated to provide high-performance slow light with a wide band, low group-velocity dispersion, and a large normalized delay-bandwidth product. Combined with structural-parameter optimization and selective optofluid injection, the normalized delay-bandwidth product could be enhanced to a large value of 0.502 with a wide bandwidth of 58.4 nm in the optical-communication window, for a silicon-on-insulator structure. In addition, the group-velocity dispersion is on the order of $10^5$ ($ps^2/km$) in the slow-light region, which could be neglected while keeping the signal transmission unchanged.


Annular photonic crystals;Slow light;Normalized delay-bandwidth product


Supported by : Natural Science Foundation of China, Natural Science Foundation of Jiangsu Province


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