| Azobenzene has good optical response properties,and its isomerization reaction can be controlled by changing external factors,such as illumination and temperature.Polymer materials containing azobenzene have been widely used in the fields of optical switches,optical storage,and biomedical applications.In addition,organic-inorganic composite materials have the advantages of both organic and inorganic components,and they not only have good toughness but also have better mechanical strength,so they have a wide range of applications in optics,electronics,and thermal fields.However,there are few related studies on introducing azobenzene into organic-inorganic composite materials at present.In this paper,azobenzene is introduced into the organic-inorganic composite materials,and the optical waveguide characteristics,optical response properties,and photochemical structure characteristics of the composite film materials are studied.The composite film material prepared in this paper has important application value in the field of integrated optics,such as optical switches and optical storage.The specific research work is as follows:（1）The azobenzene-doped GeO2-based organic-inorganic composite films were prepared by the sol-gel method,and the micro-lens array structure was fabricated on the surface by the UV nanoimprint lithography.The optical waveguide properties of the films with different heat treatment temperatures and germanium contents were studied by a prism coupler.The results show that at a wavelength of 633nm,as the temperature increases below 200℃,the refractive index and thickness of the film decrease,and the number of TE transmission modes decreases.When the heat treatment temperature is constant,with the increase of germanium content,the refractive index of the film increases,and the thickness decreases.The effects on the optical response properties of the film were investigated,such as heat treatment temperature,azobenzene concentration,and germanium content.The results show that the film has better optical response properties at a heat treatment temperature of 50℃.Furthermore,the optical switch characteristics of the film were studied by alternating exposure to UV and visible light,and the film’s optical switching performance exhibited good stability and reversibility.In addition,the Fourier transform infrared absorption spectra of the composite films with different azobenzene concentrations and germanium contents were analyzed,and the thermal weight loss performance of the composite gel material was tested.The results show that the composite material has good thermal stability within a certain temperature range.The surface morphology of the film micro-lens array was observed by an optical microscope.The results show that the micro-lenses are arranged neatly and distributed evenly.Finally,the optical imaging performance of the film micro-lens array was studied,and the results show that the hexagonal micro-lens array has better imaging performance.（2）The azobenzene-doped TiO2-based organic-inorganic composite films were prepared by the sol-gel method,and a strip waveguide array structure was fabricated on its surface by the UV nanoimprinting technology.The transmission modes of the composite film were investigated at three different wavelengths of 633nm,1312nm,and 1538nm.The results show that the film exhibits multi-mode transmission at 633nm and 1312nm,while the wavelength is 1538nm for single-mode transmission.The refractive index and thickness of the film were tested under different azobenzene concentrations and heat treatment temperatures.The refractive index and thickness of the film decrease as the heat treatment temperature increases when the temperature is below 200℃,and they gradually increase with the increase of the azobenzene concentration.The optical response properties of the composite film were studied under different azobenzene concentrations.The results show that the film with 3wt.%azobenzene concentration has good optical response properties.Additionally,the composite film exhibits good optical switch performance.Furthermore,through an optical microscope,the surface of the film was observed to have an orderly and evenly distributed arrangement of the strip waveguide array. |
