Design, Preparation And Optical Properties Of Surface Plasmon Structural Color

Surface plasmon structural color utilize plasmon resonance effects to bind light at specific frequencies into metal nanostructures and reflect or transmit light at other frequencies,resulting in different colors.Its secondary diffraction localization effect can achieve ultra-high resolution color display.It does not contain chemical elements,has stable properties and dynamically adjustable color.It is widely used in dynamic image display,information security,data storage and encryption,etc.In this thesis,we mainly studied the preparation,optical properties,and sensing performance of plasmon structured color arrays.The following are the main contents of this thesis:1.A structured color array based on a coaxial cavity is proposed,which has refractive index sensing characteristics.Surface spin coating of humidity sensitive material PVA can achieve humidity sensing.The optical properties and color rendering performance of coaxial cavities are studied using finite difference time domain(FDTD)methods.The structure is fabricated by self-assembly nanosphere,magnetron sputtering coating,reactive ion etching and other technologies.The resulting structural colors are rich and distinct.The sensitivity of the coaxial cavity array to the ambient refractive index can reach 484 nm/RIU.In addition,PVA humidity sensitive films can be spun coated on the surface of the structure to test the humidity sensing characteristics of the structure.The humidity sensitivity of PVA with spin coating concentration of 2 wt% can reach 0.949 nm/%RH,and the color changes significantly with the humidity.The combination of structural color and humidity sensing makes the coaxial cavity arrays structure have a good application prospect in environmental detection.2.The transmissive color filter based on the silver nano-aperture arrays and the reflective color display based on the ring arrays are proposed.A new method for preparing aperture structures is designed,and the structural parameters are adjusted and controlled by changing the processing parameters.Both coaxial aperture arrays and central concave coaxial aperture arrays have good color light filtering characteristics,the maximum transmission efficiency exceeds 70%.Changing the slit height and width of the structure can change the filtered transmitted wave length,thus realizing transmissive color filtering.The coaxial ring structure realized the change of etching depth through oxygen etching time,and the displayed structure color is bright and sensitive to color change,the color gamut span is large.The prepared nanostructured color device have flexible and adjustable structure parameters,low cost and can be prepared in large area.They have good color filtering and display characteristics,and have good application prospects in the fields of digital color display,optical security and information storage.The research results of several structures proposed in this thesis show that:(i)The structure color devices have high resolution and can realize color display at nanometer scale;(ii)Structural colors can be adjusted and cover a wide range.They can be adjusted by changing structural parameters through experimental parameters;(iii)The structures have high manufacturing efficiency,low cost,good stability and high order of periodic arrangement.