摘要
Herein we propose a novel strategy to enhance surface plasmon resonance(SPR)by introducing a photonic cavity into a total-internal-reflection architecture.The photonic cavity,which is comprised of a highly reflective photonic crystal(PC),defect layers,and a gold(Au)film,enables Fabry–Perot(FP)resonances in the defect layers and therefore narrows the SPR resonance width in the metallic surface as well as increases the electric field intensity and penetration depth in the evanescent region.The fabricated sensor exhibits a 5.7-fold increase in the figure of merit and a higher linear coefficient as compared with the conventional Au-SPR sensor.The demonstrated PC/FP cavity/metal structure presents a new design philosophy for SPR performance enhancement.
基金
National Natural Science Foundation of China(61575084,61805108,61904067)
Science and Technology Planning Project of Guangdong Province(2014B010117002,2017A010101013)
Science Technology Project of Guangzhou(201605030002,201704030105,201707010500,201807010077)
Joint Fund of Pre-research for Equipment,and Ministry of Education of China(6141A02022124)
Fundamental Research Funds for the Central Universities(21618404)。
