| Since the starting work that azo molecule has reversible cis-trans structure changing, Study on the polymer possessing azobenzene and polymer is booming increasingly liquid crystal, these days it is an attractive topic of nonlinear optics and its application. But in the very long time, people realized only the birefrection and polarized photograph character and so on, and that azo material has very large nonlinear optical coefficient is deduced by this way. Now for the purpose of realizing the nonlinear optical character quantificationally and comparing with the same kind of nonlinear optical materials expediently, a new type of optical storing material, the film sample of azobenzene disperse red polymer was measured by using the single beam Z-scan technique. The experimental results show that the nonlinear refractive index of the sample is a negative value. For eliminating the influence of nonlinear absorption, the Z-scan curve with an aperture was treated with the Z-scan curve without the aperture. The nonlinear refractive index of this type of azo polymer film was determinated as -5.5210-6cm2/w according to the experimental data of Z-scan curve. The value of azo polymer film is larger 8~9 scales than the common inorganic materials. This material would have a very good prospect in the application of optical storage. At last, the reason of large nonlinear refractive index in this material is discussed. It is considered a collective response just like the liquid crystal through pilot study. Under the irradiation of linear polarized beam, molecule of film has been anisotropic. These molecules liked liquid crystal phrase are linked together commendably. This molecules' response to outside trouble is a collective effect, for this reason they possess very large nonlinear response. At the same time, as an excellent optical applied material, study of station and structure of azo film on the surface of accessorial underlay is propitious to realize material's physical character deeply, and has indispensable function for optimizing the quality of material and apparatus. As a result of this, methyl yellow as a typical azo materiel has been studied by SERS spectrum technology, the enhanced Raman peak and adsorption mechanism of methyl yellow has been investigated on the surface of the rough silver that was made by the way of chemical sediment. As the experiment's result showing, adsorption station of methyl yellow is considered that: two methyls in the left of structure have physical adsorption with the surface of the rough silver. In turn the right is away from the surface of the rough silver. The structure bends at the place of the first phenyl. Twin-bend of nitrogens is almost parallel to the surface of the rough silver. The structure bends again at the place of the second phenyl. The second phenyl is vertical to the surface of the rough silver, there are physical adsorption between them.At last, for the purpose of azo property as an optical storage material the setup of measuring photo-induced birefraction of azo has been bettered on the base of primary work. Primary academic deduction shows that the improved setup can gain more accurate experimental result. At the same time, polarized holography experiment of azo material has been done, the sample has been found prominent polarized sensitive character. And polarized holography image that has been produced using two vertical linear polarized beams has been recorded, its diffractive efficiency is 19.3%. The sample has not presented evident fatigue, this material has been proved an ideal material for recording polarized holography.
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