Optimizing slow light parameters in 2D-heterostructure photonic crystals with circular and square rods and holes

Abstract

Theoretically, we aim to optimize the parameters related to slow light in a 2D heterostructure photonic crystal. Two types of heterostructures were investigated by joining two photonic crystals: one composed of square holes and the other with circular rods or vice versa. The plane wave expansion and supercell method are used to analyze the waveguide mode. Germanium is assumed to be the material for the rods and background. The group index and bandwidth for the waveguide appearing at the interface were optimized. A comprehensive survey of rod and hole size values reveals that the achieved group index bandwidth product of 0.72 is primarily due to the high bandwidth achieved within the optimized structure. Furthermore, our results confirm that rotating the square rods can further enhance slow light parameters, leading to a significantly higher group-index-bandwidth product than traditional semiconductor photonic crystal waveguides.

Keywords:

• 2D photonic crystal
• plane wave expansion method
• slow light
• group index
• bandwidth

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The authors confirm that the data supporting the findings of this study are available within the article.

Additional information

Funding

This work was supported by a 2020 Yeungnam University research grant.