Research Of Optical Buffer Based On Surface Plasmon Coupled Micro-cavity

In recent years,the research of integrated slow-light devices has attracted extensive interest at home and abroad.Surface plasmon device can realize subwavelength localization,and greatly improve the integration of photon system.Slow-light technology has been bringing the new opportunity for the fabrication of optical signal buffer device,which is of great significance to future all-optical network.In recent years,the research of slow light technology is in the ascendant at home and abroad.And the surface plasmon waveguide slow-light waveguide has received the extensive attention,because of the double features of reducing the speed of light and realizing the subwavelength localization,becoming one of the best of these technologies.We investigated the plasmon-induced transparency(PIT)and slow-light properties in a plasmonic single-mode and two-mode resonators coupled system.We mainly finished the following work:1.We designed the plasmonic single-mode and two-mode resonators coupled system.Our structure is first time to be put forward,generating different from traditional bare-state PIT effect,it originates from the destructive interference between a radiant standing-wave mode in the slot cavity and two subradiant travelling-wave modes in the ring resonator.2.A theoretical model is established to describe this PIT system,and the analytical results agree well with the numerical simulations.The difference between our structure and similar coupled-resonators structures is shown.The transparency window can be tuned by adjusting the structural parameters,and two types of PIT lineshape are discussed in detail.The numerical results reveal that,the PIT window with weakly resolved and equal doublet peaks exhibits high-performance slow light.A delay-bandwidth product larger than 1 and ultra-low dispersion are obtained,and a delay of 1 bit with negligible pulse distortion is achieved in the proposed system.3.We further studied the cascaded structure using ring-bus-slot structure as a unit cell,through adjusting the spacing between two adjacent unit cells,it can be found that the saddle line shape of PIT window changes into the corrugated,the passband becomes more wider,and the top of the pass band becomes more flater.To verify the transmission properties of the PIT,we also establish the theoretical model including the coupled mode theory and transfer matrix theory.Then the slow light characteristics is further researched,we theoretically obtained outstanding slow-light characteristics of new plasmon waveguide.The proposed configuration is more likely to have important potential applications in photonic integrated system such as optical switch,optical value.