摘要
In this paper,we describe a new method to improve fast-light transmission,which uses cascades.We design a simple plasmonic device that enables plasmonic-induced absorption(PIA).It consists mainly of two parallel rectangular cavities.The numerical results simulated by using the finite element method(FEM)confirm its function.The corresponding group delay-time can reach-0.146 ps for the PIA window.Based on this result,we propose a cascade device,with the dual-rectangular cavity system as building block,to improve fast-light transmission even more.The results indicate that the cascade scheme can increase the group delay-time to-0.456 ps,which means the fast-light feature is substantially enhanced compared with the non-cascading approach.The effect of the distance between two cascade resonators and other structural parameters is also investigated.Finally,we use this design concept to build a refractive-index sensor with a sensitivity of 701 nm/RIU.
基金
supported by the National Natural Science Foundation of China(Grant No.61367007)
the Natural Science Fund of Gansu Province of China(Grant Nos.17JR5RA123 and 17JR5RA132)
the HongLiu First-Class disciplines Development Program of Lanzhou University of Technology.