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用Cu离子交换技术制备了玻璃平面光波导,利用IWKB法与离子浓度计算折射率的方法结合,得到了Cu 和Cu2 相对应的折射率分布.当离子交换深度较深时,折射率变化主要是由Cu 引起,且折射率变化较小;而当深度较浅时,折射率变化则是由Cu 和Cu2 共同作用的结果,而Cu2 的对折射率变化的贡献集中在玻璃表面.通过离子浓度计算得出5 min交换时间的折射率分布呈现准梯度折射率分布形状,而随着离子交换时间的增加所制备的平面波导通过棱镜耦合无法测到波导模式,这可能是由于波导表面折射率下降所致,其机理可能是由于Cu 的外扩散和大离子直径的Cu2 在玻璃表面附近产生的应力在高温下退火被释放的共同结果. 相似文献
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高斯折射率分布Cu+-Na+离子交换玻璃波导的制备 总被引:3,自引:1,他引:2
利用Cu+ Na+ 离子交换技术制备了玻璃平面光波导 ,在 6 32 8nm波长下 ,用棱镜耦合技术测量出所制备波导的有效折射率 ,利用反WKB方法确定了平面光波导的折射率分布 ,并对折射率分布进行了函数拟合 ,近似符合高斯分布。求出了所制备玻璃平面光波导在 5 80℃的扩散系数为De ≈ 2 2 2 3× 10 -15m2 /s。 相似文献
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用Cu离子交换技术,制备了soda-lime玻璃平面光波导。通过棱镜耦合技术测量了波导的有效折射率,用反WKB方法拟合得到了平面波导的折射率分布。研究发现,离子交换时间和温度2个可控的制备参数对制备的玻璃平面波导特性有较大影响,随着离子交换时间和温度的增加,波导的模式数和波导深度并非随之单调增加,波导模式数随着离子交换时间的增加先增加而后减小,而适当的离子交换时间可以使制备的波导具有最大的模式数和波导深度,且在该条件下增加离子交换温度可以提高Cu离子交换波导的蓝-绿发光强度,宽带发光中心波长在520 nm附近,发光强度取决于样品中Cu+的浓度以及Cu2+的影响。 相似文献
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为了实现一个表达式同时反映Y分支光波导在纵横两方向上的折射率分布,通过对玻璃结构和离子交换过程进行分析,采用逆向分离变量法提出了基于横向和纵向两个方向折射率分布函数乘积的横截面折射率分布函数,并利用MATLAB软件对优化结果进行了编程模拟。利用Tl+-Na+离子交换法在BK7玻璃基底上制备了Y分支12型3维光波导,利用雅明干涉法对光波导横截面的折射率分布进行了测量。结果表明,利用改折射率分布函数模拟得到的Y分支光波导横截面折射率分布与雅明干涉法实验测得的结果吻合。该改进型折射率分布函数可以对Y分支光波导横截面折射率分布进行模拟,能准确快捷地对Tl+-Na+离子交换Y分支3维光波导横截面折射率分布进行重建。 相似文献
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两步离子交换低损耗光波导功分器的研制 总被引:1,自引:1,他引:1
报道了在热扩散条件下两步离子交换玻璃光波导功分器的理论分析、样品制作和实验测试.为了便于定量分析,采用了一种上升反正弦S型分支光波导系统的物理模型,得到了在热扩散条件下两步离子交换光功分器波导区的归一化折射率分布和在不同交换时间所形成的玻璃波导折射率分布.在此基础上,设计和制作出第一步采用含Tl 纯熔盐Tl2SO4与玻璃含Na 进行离子交换形成表面下半圆形波导,再把该波导表面脱钛膜放入含Na 熔盐NaNO3中进行第二步离子交换形成掩埋式圆形波导光功分器,实现插入损耗为0.15 dB和分光比为50:50的上升反正弦S型玻璃光波导功分器. 相似文献
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本文报道用不同离子两步交换技术,在玻璃衬底上制作K~+离子交换掩埋波导的新工艺,它不要求施加外电场。用X射线能谱(XES)分析技术测试了K~+离子的浓度分布,证明所制出的样品是掩埋波导。 相似文献
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本文报道了用TI盐(TI_2SO_4)离子交换法制备玻璃光波导的实验结果。与用AgNO_3离子交换制备的光波导相比,波导损耗较低,折射率分布呈准阶跃型,拟合确定其折射率分布函数为费米函数,折射率增量Δn>0.13。 相似文献
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Low-loss (0.1 dB/cm at 632.8 nm) waveguides fabricated in BK7 optical glass using the transverse electromigration of Ag+ ions are discussed. With a migration time of 1.5 h at 320°C, waveguides of depths from 3.0 to 5.0 μm were obtained with various index changes. The inverse WKB method was used to deduce the index profile. The profile was further confirmed by a comparison of experimental and theoretical mode indices and intensity distributions 相似文献
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Miliou A. Zhenguang H. Cheng H.C. Srivastava R. Ramaswamy R.V. 《Quantum Electronics, IEEE Journal of》1989,25(8):1889-1897
A systematic study of waveguides fabricated by K+-Na + exchange in soda-lime silicate and BK7 glasses is presented. The measured K+ concentration profile, the refractive index profile, and the diffusion profile obtained by solving the one-dimensional diffusion equation are correlated to explain the differences in the index profiles in the two glasses. The mobility of the potassium ions was measured by fabricating waveguides using electromigration. Surface waveguides formed by diffusion from a molten KNO3 salt bath were buried by applying an electric field. Single-mode channel waveguides for operation at a wavelength of 1.3 μm that exhibit excellent mode matching with conventional optical fibers, achieving a fiber-waveguide insertion loss of less than 1 dB for a 20-mm-long waveguide, have been obtained 相似文献
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Planar graded index optical waveguides have been formed by K+ ion exchange in BK7 optical glass and Pyrex glass. Measurements of the mode indexes have been made and are well described by the WKB dispersion relation with a complementary error function refractive index profile for both glass types with refractive index changes (Delta n ) of 0.0094 and 0.0073 for BK7 and Pyrex, respectively. A linear relation was found between the diffusion depth and the square root of the diffusion time for both materials, and effective diffusion coefficients were calculated. Diffusion times necessary to achieve a desired number of modes and diffusion depths have also been established. 相似文献
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This report focuses on research into waveguides prepared by K+-Na+ ion exchange with the help of an electric field, and the subsequent comparison with waveguides prepared by pure thermal ion
exchange. The goals of this work were to determine the characteristics of and to address the technological problems associated
with waveguides prepared in two types of highly pure optical glass: special soda-lime silica GIL49 glass produced from pure
raw materials and commercially prepared borosilicate BK7 glass. An appropriate chemical mixture, KNO3:Ca(NO3)2 in the molar ratio of 41:59, was used as the source of potassium ions. Experiments were conducted at temperatures between
250 and 410°C, and electric field values between 0 and 150 V/mm. The number of modes, depth, profile, and the change in refractive
index (Δn) were measured for samples from each type of glass under various technological conditions. All of these parameters
can be controlled accurately and repeatedly by the electric field. These experiments have also shown that a particular advantage
of these types of pure glass is the low waveguide optical losses (0.1 to 0.2 dB/cm) attainable. 相似文献