Детальний аналіз елемента призмового сенсора, що працює на явищі поверхневого плазмонного резонансу

Abstract

Виконано числовий аналіз оптичних характеристик елемента призмового сенсора, що працює на явищі поверхневого плазмонного резонансу, залежно від його геометричних параметрів, джерела зовнішнього опромінення та показника заломлення навколишнього середовища. Отримано оптимальні геометричні параметри сенсорного елемента для досягнення максимальної чутливості сенсора. Виготовлено та досліджено макет сенсорного елемента. Між експериментальними та теоретичними результатами добра кореляція.The theoretical research and experimental verification of the surface plasmon resonance prism based sensors element have been carried out. This research includes the simulation of optical characteristics, optimization of geometric parameters and the production and research of an experimental low cost prototype with simple construction. The influence of the thickness change of the silver and chromium layers on the position of the reflectance minimum, which corresponds to the surface plasmon resonance, has been investigated. The change in the thickness of the silver layer affects on the position of the surface plasmon resonance, the value of the reflectance in the minimum and the curve shape. The change in the thickness of the chromium layer practically does not affect on the position of the surface plasmon resonance. However, it should be noted that the thickness of the chromium film affects on the value of the reflectance minimum and the curve shape. It is founded that the smaller the wavelength of the radiation source will correspond to the greater the angle of the surface plasmon resonance. The dependences of the reflectance on the change in the refractive index of the studied gas and water media with different refractive indices were simulated. The optimal parameters of the sensor element with enhanced sensitivity have been determined. A prism based sensors element was produced. The experimental scheme of investigation optical characteristics of the prism based sensors element was developed. There is a good correlation between theoretical and experimental results.