Optical Properties Of Vanadium Dioxide-Silver Nanoparticles Subwavelength Array Composite Structures

In recent years,metal subwavelength structures have been widely studied because of their special electromagnetic properties.It has been often used in the fields of electromagnetics and optics.Compared with the traditional microstructure,the spectral response of the subwavelength structure to the electromagnetic wave is not only related to the material properties of the structure itself,but also to the design of its morphological structure and the composition of its structural units.Therefore,the artificial subwavelength structure can be used to control the electromagnetic wave more accurately.The special electromagnetic characteristics of subwavelength structure can realize the functions that traditional materials and structures cannot achieve,such as frequency selection,polarization regulation and beam shaping.However,once its structure of the traditional subwavelength structure is qualitative,the function is often determined,the working wavelength is limited and the function is single.This paper introduces the spectrum response and regulation principle of sub-wavelength structure.Using the principle of light-controlled assembly fabricated silver nanoparticle arrays with a period of sub-wavelength.Their optical properties under air and prism excitation are studied and introduced.Regulated phase change material.A phase change material-noble metal subwavelength array composite structure with dynamically adjustable spectrum response was prepared,and its optical characteristics before and after vanadium dioxide phase change were tested.The main research work of this article includes the following:1.Based on the research progress of sub-wavelength devices at home and abroad,this paper introduces the physical mechanism of sub-wavelength devices,the classification of sub-wavelength devices and the research progress of phase change material-sub-wavelength composite devices,and then explains the basis of the topic.2.According to the properties of nanometer vanadium dioxide materials,the material properties of vanadium dioxide are introduced and the thermally and electrochemically induced phase transitions are described.Next,we introduce the classification of the plasmon and common excitation methods,and introduce how to use phase-change materials to adjust the spectral response of the plasmon.Then the field distribution and light field force distribution of laser evanescent standing wave were simulated by the Matlab.3.X-ray diffraction analysis(XRD)of nano-vanadium dioxide was performed and prepared vanadium dioxide films.The transmittance of vanadium dioxide films before and after the phase change was tested.Then,the sub-wavelength silver nanoparticles array constructed by laser evanescent standing wave was characterized by scanning electron microscope,and its optical characteristics were tested by macroscopic angular resolution spectrometer under the excitation in the prism and external incident scattering modes.4.A composite structure of vanadium dioxide-silver nanoparticle array was prepared,the basic principle of the prism excitation mode was introduced.Test the spectral response of the noble metal sub-wavelength array before and after the vanadium dioxide phase transition in the prism excitation mode and the external incident scattering mode.