Surface Plasmon Resonance Sensor Enhanced By Hyperbolic Metamaterials Composed By Alternative Metal/Dielectic Medium

Because of the advantages of high-sensitivity,label-free and real-time dynamic detection,surface plasmon resonance?SPR? sensor has been widely used in medical detection,food safety,drug screening,environmental detection and many other fields.For a long time,the research direction of plasmonic sensing technology is to improve the sensitivity and figure of merit?FOM? of SPR sensors,so that it can break through the detection limit of detection of the small molecules,the analytes with ultralow concentration and weak intermolecular affinity.After summarizing the existing research status of SPR sensors at home and abroad,due to the special hyperbolic dispersion characteristics,hyperbolic metamaterial?HMM? can effectively improve the performance of the sensor by adjusting the material dispersion and supporting high-k mode.This paper puts forward a new type of metal/dielectric multilayer film HMM modified SPR?HMM-SPR?sensor.At first,the principle of improving the performance of the sensor is analyzed theoretically;then the optimal design parameters of the sensor are calculated by simulation;finally,according to the optimized results,the sensor device was fabricated and characterized.The contents of this dissertation are summarized as follows:?1?Theoretical analysis of SPR sensor based on hyperbolic metamaterial enhancement.The equivalent medium theoretical model of HMM-SPR sensor is presented and the permittivity of the equivalent hyperbolic metamaterial is taken into the resonance condition of SPR to calculate the sensor sensitivity.The effects of incident angle,composition of hyperbolic metamaterial and metal filling fraction on sensor sensitivity are calculated theoretically.?2?Design and optimization of HMM-SPR sensor using transmission matrix method.Firstly,the transmission matrix method and corresponding software used in the simulation design are introduced,and then the optimal design of the incident angle of light,the structural parameters and the component materials of the metal-dielectric multilayer hyperbolic metamaterial is selected by the simulation software.The results show that Ag and ZrO₂ are used to form hyperbolic metamaterial in the range of refractive index of 1.33-1.34 RIU.When metal filling fraction of structural parameters is 0.5,bilayer of hyperbolic metamaterial is 3,thickness of the single pair of bilayer is 30nm and incident angle of sensor is 65°,the HMM-SPR sensor has the best performance:sensitivity can be as high as 64000 nm/RIU,and FOM is 477.6 RIU^-1.?3?Experimental study of HMM-SPR sensor.According to the optimization results of simulation,the HMM-SPR sensor was prepared by vacuum deposition technology.In the sensor's refractive index test experiment,the sensor perform an average sensitivity of 16464.07 nm/RIU and an average of FOM of 106.48 RIU^-1,with refractive index ranged from 1.331 to 1.343 RIU.Compared with SPR sensor based on 50 nm gold film,sensitivity was increased by 8.17 times and FOM by 5.18 times.The innovation of this dissertation lies in:?1?In this paper,theoretical calculation and sensitivity analysis of HMM-SPR sensor are proposed by matching the equivalent medium theory with SPR resonance conditions.The advantage of this method is that through simple theoretical calculation,the sensitivity of SPR sensors in different situations can be predicted quickly,and the theoretical analysis and simulation results can be verified mutually,which is conducive to the accuracy of simulation design.?2?The HMM-SPR sensor proposed in this paper takes advantage of multiple SPP interactions and dispersion regulation in hyperbolic metamaterial to improve the performance of the sensor.Compared with conventional sensors,the sensitivity,full width at half maximum,and figure of merit of the sensor are significantly improved.?3?The Kretschmann structure HMM-SPR sensor proposed in this paper,compared with the hyperbolic metamaterial sensors of grating coupling and nanorods type,has lower cost,simpler manufacture and high controllable precision,which is expected to be further applied to fiber optic sensors.