title: Surface plasmon resonance sensor based on spectral interferometry: numerical analysis.
abstract: In this paper, we introduce a numerical simulation of a phase detecting surface plasmon resonance (SPR) scheme based on spectral interference. Based on the simulation, we propose a method to optimize various aspects of SPR sensors, which enables better performance in both measurement range (MR) and sensitivity. In the simulation, four parameters including the spectrum of the broadband light source, incident angle, Au film thickness, and refractive index of the prism coupler are analyzed. The results show that it is a good solution for better performance to use a warm white broadband (625-800 nm) light source, a divergence angle of the collimated incident light less than 0.02°, and an optimized 48 nm thick Au film when a visible broadband light source is used. If a near-IR light source is used, however, the Au film thickness should be somewhat thinner according the specific spectrum. In addition, a wider MR could be obtained if a prism coupler with higher refractive index is used. With all the parameters appropriately set, the SPR MR could be extended to 0.55 refractive index units while keeping the sensitivity at a level of 10(-8).
authors.affiliation: Optoelectronic System Laboratory, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.
authors.forename: Yunfang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.forename: Jingyuan
authors.initials: J
authors.lastname: Duan
authors.forename: Ancun
authors.initials: A
authors.lastname: Shi
authors.forename: Yuliang
authors.initials: Y
authors.lastname: Liu
mesh_terms: D003198:Computer Simulation; D017076:Computer-Aided Design; D007368:Interferometry / Q000295:instrumentation*; D008027:Light; D008962:Models, Theoretical; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D014159:Transducers