Water Trace Pollutants In Surface Plasmon Detection Technology Research And Experiments

Trace polluted substances detection techniques based on surface plasmon polartions (SPP) is an interdisciplinary optical research field. It comprises of optical surface plasmon resonance techniques, small signal detection techniques, optical system design, metal film deposition techniques, small signal processing. Portable field polluted substances detection device based on surface plasmon polarions is a novel optical sensor system. It changes the status that the typical SPP sensor system is too ponderous and high requirement on environmental condition, make the SPP sensor device system step out of the laboratory and become a pratical field online inspection device.The theory innovations of this dissertation include the following: The Ag-Au bi-metal SPP sensor structure is presented. The Fortran language is used for programming to simulate and optimize the structure parameters to improve the performance on sensitivity and linearity, and the device life period is also lenthed by the improvement of adhesion intensity. A novel Mach-Zehnder sensor structure enhanced by SPP is investigated. The sensitive region of the waveguide is covered with a thin Au layer. The sentivity is highly improved by SPP effect and two times higher than the typical MZ structure. The surface wave theory of negative refractive index material and its sensor feasibility are studied. The condition of existence of surface wave using negative refractive index materials is solved using the rigorous electromagnetic wave theory. Ii is shown that the surface wave can be produced for both polarizations using negative refractive index material.The experimental works of this dissertation include the following: the whole sensor device system of portable SPP traced polluted substances detection is completed. The work on optical system design and setup, control circuit fabraication and relevant software programming are finished. The detecting range of our system is 1.18-1.35(RIU) and the precision is about the scale of 10~-6(RIU). The experiments based on the device we designed are performaned and the experimental results are also discussed. Several data processing methods are compared and analysised. Duringthe periond of research the adherent processing techniques of large scale optical surface is reported, and bi-metal film desposition parameters and processing techniques are presented in this dissertation.