| Nonlinear optical material has important application prospect in optical switching, optical limiting, photo-communication and optical computing and other fields, which has aroused extensive research and has been made many notable achievements in this field. All along, the third-order nonlinear optical materials involved organic materials, metal nanoparticles, no-class semiconductor, nonlinear crystals etc. but most of these materials have a large nonlinear refractive index, nonlinear absorption or multi-photon absorption and the response is slow. But ferroelectric ceramics have a range of new and unique advantages in their optical nonlinearity, The ferroelectric ceramics precisely and becoming one of the researching hotspots in nonlinear optical materials. The ferroelectric ceramic materials have not only good nonlinear properties bua also ferroelectric and fluorescence properties. However the research time of this kind of materials is shorter, The deposition conditions of the thin film has a great impact on performance, There are many new phenomena and laws to be in-depth study. In this article, we prepared the Bi1.95La1.05TiNbO9 bismuth layered ferroelectric ceramic thin films by ourselves, we have studied the nonlinear optical properties, photoluminescence and ferroelectric properties in-depth, mainly works as follows:First, the preparation and characteization of bismuth layered ferroelectric ceramic thin film Bi1.95La1.05TiNbO9.We prepared the bismuth layered ferroelectric ceramic thin film Bi1.95La1.05TiNbO9 by pulsed laser deposition (PLD) technique. The thin films deposited on the quartz substrate and Pt(111)/Ti/SiO2/Si substrate, respectively. We related its structure characterized by using XRD diffraction, absorption spectroscopy, atomic force microscope,Second, the study of the linear and nonlinear optical properties of Bi1.95La1.05TiNbO9 thin films deposited on quartz substrate.We studied the linear and nonlinear optical properties of Bi1.95La1.05TiNbO9 thin films deposited n quzrtz substrate under the different perparations by using the Z-scaning technoloty. We analysised the effects of different deposition time, the different morphology on the nonlinear optical proplerties of materials and revealsed its inherent laws. We obtained the best nonlinear properties of the thin films deposited for 45 min. the real and imaginary parts of the third-order nonlinear optical is 9.56×10-9 and -3.67×10-9 respectively,nonlinear refraction coefficient is 7.21×10-15 and the third-order polarization rate is 1.02×10-8.the Z scan results show that the Bi1.95La1.05TiNbO9 ferroelectric thin films have potential applications on nonlinear optical. (Our studies in this section were published in《Journal of Materials Research》, May 14, 2011, 26(9) 1159-1163)。Third the study of the ferroelectric and fluorescent propertiesf of Bi1.95La1.05TiNbO9 thin films deposited on Pt (111)/Ti/SiO2/Si substrate.We studied in detailed the photoluminescence and ferroelectric properties of the Bi1.95La1.05TiNbO9 thin films deposited on Pt (111)/Ti/SiO2/Si at different annealed temperature. The results showed that the absorption and fluorescence spectra of the samples have blue shift phenomenon with the increasing annealed temperature. The particle size increased with the increased annealing temperature, the ferroelectric properties have been greatly improved. The 2Pr and the 2Ec values at 650, 700 and 750 oC are 25.49, 38.2, 44.57μC/cm2 and 421.2, 376.4, 338.5 kV/cm, respectively. ( submitted )We discussed the perparation, structure and nonlinear optical characterization of the Bi1.95La1.05TiNbO9 thin films deposited on quartz substrate. We found that the thickness of the films deposited for 30, 60 min is too thin or too thick, which does not meet the conditions of the Z scan of the far field. In addition we also discussed the fluorescence and ferroelectric properties of the Bi1.95La1.05TiNbO9 thin films deposited on the Pt (111) / Ti/SiO2/Si at different temperature, we found that the fluorescence and ferroelectric properties is the best at 750 oC.
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