光波导理论研究现状

光波导可以被广泛应用在集成光学各个领域。对各种光波导的理论进行分析,并在此基础上提出更有效和更简便的理论分析方法,从不同的宏观角度出发,不同程度地回答光在光波导中传输时的行为及其构成等基本问题,对光波导理论的研究具有重要的实际意义。     

上海硅酸盐所在平面波导激光陶瓷研究中取得系列进展

正集成光学中的光波导结构,对激光增益介质的几何形状设计是一种启示。波导结构是介质衬底表面上或内部形成的折射率相对较高的微型区域,这一区域被折射率较低的区域包裹,从而能将光限制在微米量级的结构内进行传输。将光波导结构应用于激光增益介质,其最大特点是它能够有效地限制光束发散,提高     

离子交换氟氧化物玻璃平面光波导的制备与折射率分布

用Ag -Na 离子交换法,制备了氟氧化物玻璃平面光波导.应用棱镜耦合技术测量光波导的有效折射率,通过Inverse Wentzel-Kramer-Brillouin法计算了有效折射率对应的各阶模深度,并采用Gaussian函数对其分布进行拟合,结果显示:不同交换时间下折射率最大改变量为0.0367,离子交换扩散系数为0.012 μm2/s.探讨了交换时间对氟氧化物玻璃平面光波导性能的影响.     

获得蓝色激光的方法

迄今为止,实现全固体蓝色激光光源的途径主要有四种,即直接发射蓝光的LD、LD倍频的蓝色光源、蓝色波导激光器和利用LD泵浦,并通过非线性光学手段获得的蓝色激光器。 1.直接发射蓝光的半导体激光器 此类蓝光激光器主要特点是结构简单、使用方便、电-光转换效率高等优点。最先的研究主要集中于Ⅱ—Ⅳ族材料尤其是ZnSe上。这种材料禁带宽度约2.7eV,发射波长相应于深蓝色     

光束传播法在光波导中的应用

近几年来出现了一些分析集成光波导的数值分析方法,在这些方法中,光束传播法是分析光波导器件的一种有效的方法。本文简单介绍了光束传播法的发展概况和基本计算思路,并利用有限差分光束传播法模拟出了脊波导半导体激光器的剖面,使光束传播法得到了广泛的应用。     

超快激光在玻璃内部直写纳米晶及其应用

超快激光直写技术由于其灵活性、高效性和良好的方向性,可以三维选择性地在材料内部进行加工,被广泛应用于玻璃的微晶化及其器件的制备中,在光储存、波导激光器、光子电路和集成光子芯片等领域有着广泛的应用前景。本文简要概述了超快激光在玻璃内部诱导析晶的原理,晶态/非晶态自组织周期性结构的形成机制,以及超快激光在玻璃三维空间中诱导析晶的最新研究进展,总结了通过控制激光参数和玻璃成分等实现对结晶形态、结构及光学性质调控的相关研究,并对所直写的微纳结构在非线性器件、光储存、激光器等领域的应用和发展方向进行了概述与展望。     

集成高分子光子学器件平台

在高分子基板上制作成的单膜全氟高分子波导结构,具有非热敏感性、偏振无关的工作特点,同时,在1310nm、1550nm工作波长分别有<0.04和<0.05dB/cm的超低光损耗.本文研究了在器件制作过程中所产生的孔状结构对传输损耗的直接影响.实验证明,超低的传输损耗可以通过降低孔状结构的尺度至纳米范围来实现.这些波导结构可以成为新一代高性能集成高分子光子器件的技术平台.     

3D打印成型陶瓷零件坯体及其致密化技术

3D打印技术在陶瓷零件成型方面具有较大应用潜力,被认为是近净尺寸成型高性能复杂结构陶瓷零件的一种新途径。本文比较了陶瓷零件或其坯体的激光选区熔化、薄材叠加制造、熔融沉积造型、光固化、三维打印和激光选区烧结等不同3D打印工艺及其致密化手段的优势和不足,认为较低的相对密度和强度是阻碍3D打印陶瓷零件实现产品应用的主要障碍。本团队近年来采用造粒混合法制备出具有良好流动性的3D打印复合陶瓷粉体,再通过激光选区烧结(SLS)和冷等静压(CIP)技术分别进行坯体成型及均匀致密化处理,制备出了高性能、复杂结构的Al_2O_3致密陶瓷零件。本文回顾了这些工作,并补充介绍了溶解沉淀和溶剂蒸发这两种制备复合陶瓷粉体的新方法,利用SLS/CIP复合工艺进一步制造了ZrO_2、SiC、高白土等其它材质的复杂陶瓷零件,为3D打印陶瓷用于航空航天、医疗、艺术等领域奠定了基础。     

KTiOPO4晶体条状波导的制备和研究

报道了以离子交换法制备KTiOPO_4晶体条状波导的结果,成功地获得了1.3μm,0.73μm和0.6328μm单模波导,测量了其光强分布及对1.3μm激光衰减系数。     

若干无机/有机复合光功能材料及相关器件研究进展

在无机基质中光学均匀掺杂有机光添生物质以获得复合光功能材料是近年来的研究热点,复合光功能材料的溶胶－凝胶低温合成技术为其在非线性光学、固态可调谐染料激光器、发光显示、光致变色、光化学烧孔等领域的应用提供了可能。本文对无机／有机复合光功能材料的制备技术、结构与性能的表征手段,及其作为发光、激光、波导、波分复用、光致变色器件在光通信中的应用等研究进展作了评述。     

Self-Assembled Alkynyl Azoles and Benzoazoles as Colored Optical Waveguides

Different alkynyl azoles and benzoazoles have been synthesized in good yields by carbon-carbon coupling reactions. The self-assembly of some of these compounds by the slow diffusion technique led to well-defined ribbons and needle-like aggregates. The X-ray study of some materials showed that the CH-π interactions involving the C≡C triple bond and the heteroatoms induce aggregation along with H-bonds due to the methoxy groups. A fluorescence and confocal optical microscopy study of most of the aggregates indicated optical waveguide behavior with different colors.     

A novel polycarbonate composite for waveguides

The novel polycarbonate resin compositions comprising polycarbonate (PC) and acrylic resin were prepared by solution blending and analyzed by differential scanning calorimetry, atomic force microscopy, gel permeation chromatography, and gas chromatography‐mass spectrometry. Furthermore, the optical performance and the thermal and mechanical properties were tested, respectively. The results demonstrate that the blended material which was prepared by 100 parts of PC and 0.05 parts of acrylic resin achieves excellent transparency in blue‐light region (280–400 nm). Meanwhile, it retains excellent high‐heat resistance and mechanical performance of PC. Because of its high transparency in the blue‐light region which is caused by a doping of a tiny amount of acrylic resin, this material takes steps towards solving the optical problem that light becomes yellow when leaving the end of waveguides of PC. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46529.     

Polymer thin film photodegradation and photochemical crosslinking: FT-IR imaging, evanescent waveguide spectroscopy, and QCM investigations

Photodegradation and photocrosslinking of benzophenone blended polystyrene (PS) thin films were investigated primarily using Fourier transform infrared (FT-IR) imaging, evanescent waveguide spectroscopy (WS), and quartz crystal microbalance (QCM) methods. The main objective is to observe the changes (spectral and chemical) indicative of these competitive processes in an ultrathin polymer film. This also serves as a model study in the application of combined spectroscopic, optical, and acoustic methods towards understanding crosslinking and degradation phenomena within the same time frame of observation. To induce photocrosslinking, 1,12-dodecanediylbis(oxy-4,1-phenylene)] [bis[phenylmethanone] (2BP12), a small molecule with two benzophenone groups, was blended with PS in solution, spincast onto glass and silicon substrates, and irradiated with ultraviolet light. Photodegradation and benzophenone-mediated crosslinking were observed both directly via functional group spectroscopies and indirectly via their effects on thin film surface properties and morphologies. Atomic force microscopy (AFM) and QCM were used to elucidate local morphology change and mass-uptake kinetics in the presence of O₂ in air, respectively. All results correlated well with the two photoprocesses occurring simultaneously and competitively on these films with the refractive index, thickness, and mass change differing with the presence of 2BP12. Crosslinking was observed to cause an increase in thickness while photodegradation gave a decrease. Both processes resulted in an increase in the refractive index and mass. While various methods have separately identified these observations, this is the first instance that the in situ chemical, optical, and structural dimensionality of the photodegradation and photocrosslinking phenomena in a thin polymer film is correlated within the same time frame of observation.     

Synthesis, characterization and optical properties of cross-linkable poly(phthalazinone ether ketone sulfone)

Cross-linkable poly(phthalazinone ether ketone sulfone) bearing tetrafluorostyrene groups (PPEKS-FSt) has been prepared by copolycondensation reaction for optical waveguide applications. The resulting amorphous polymer exhibits good solubility in some common polar organic solvents (e.g., N,N′-dimethylacetamide, N-methyl-2-pyrrolidinone, chloroform) at room temperature, and can be easily spin-coated into thin films with good optical quality. The glass transition temperature (T_g) and the temperature of 1% weight loss (1% T_d) are 261 °C and 494 °C, respectively, which could be further increased by 31 °C and 14 °C upon thermal cross-linking. The cross-linked polymer thin films exhibit high refractive index (∼1.65, TE mode), high thermo-optic coefficient value (dn/dT) (−1.455 × 10⁻⁴/°C, TE mode), low optical loss (less than 0.24 dB/cm at 1310 nm) and relatively low birefringence (∼0.007).     

二氧化硅基波导薄膜的制备方法综述

总结了目前制备二氧化硅基波导薄膜的各种制备工艺，包括广泛采用的等离子增强化学气相沉积法（PECVD）、火焰水解法（FHD）、低压化学气相沉积法、溅射法、离子交换法、离子注入法和溶胶-凝胶法等制备方法，并对各种工艺的原理、特点和应用现状进行了详细的介绍。     

钽酸锂晶体波导基片光损伤的研究

用硅钼棒作加热体，用熔体提拉法生长了ＬｉＴａＯ３晶体，晶体的双折射梯度可达１０＾－５ｃｍ＾－１数量级。用质子交换法制作了ＬｉＴａＯ３光波导基片，其抗光损伤能力高于ＬｉＮｂＯ３，是优良的杨光学和非线性光学材料。     

Hyperbranched fluorinated polyimides with tunable refractive indices for optical waveguide applications

A series of halogenated hyperbranched polyimides (HBPIs) with tunable refractive indices (RIs) has been designed and prepared for use as novel optical waveguide materials. The hyperbranched structure of these polymers leads to multifarious and controllable chemical structures. The degree of branching in these HBPIs was estimated using ¹H NMR spectroscopy. The halogen-terminated HBPIs were found to exhibit high glass transition temperature, good thermal stability, excellent transparency, low birefringence and low optical loss in the wavelength windows for telecommunication. Due to the high polarizability of the C-Cl bond at the terminal groups, RIs were precisely controlled by adjusting the C-Cl bond content without additional optical losses. Finally, several waveguide devices were fabricated by the reactive ion etching (RIE) technique and were found to exhibit good optical propagation at a wavelength of 1.55 μm.     

新型硫卤玻璃GeS2-Ga2S3-AgX(X=Cl,Br,I)中的K+-Ag+离子交换

以油酸钾为熔盐,GeS2-Ga2S3-AgX(X=Cl,Br,I)玻璃为基玻璃,在270℃的环境温度下,以氮气作为保护气氛,成功地进行了K -Ag 离子交换。在50GeS2-25Ga2S3-25AgI玻璃中,K 离子的交换深度可达256μm,并对交换深度、离子扩散系数以及离子浓度之间的规律进行了初步研究。通过离子交换研究,为制备硫卤玻璃光波导奠定了基础,并可以进一步拓宽硫卤玻璃的应用前景。     

波导对橡胶微波加热硫化的影响

采用ANSYS有限元分析软件分别模拟橡胶在圆波导和同轴波导两种模式下的微波加热硫化过程。结果表明:同轴波导模式下胶料的微波加热效率低于圆波导模式,但同轴波导模式下胶料经微波加热后,胶料的最高和最低温度的差值较小,即同轴波导模式下加热胶料内的温度分布较均匀。