共查询到19条相似文献,搜索用时 140 毫秒
1.
分析了导模-辐射模耦合理论和利用经塔米尔的传输回路方法论改造过的扰动理论进行解析的结果。根据上述理论对1.3μm GeSi/Si异质结波导光栅耦合器波导层的厚度、槽形、长度、宽度、周期、槽深等做了近似的设计。 相似文献
2.
介绍了一种新颖的自聚焦平板波导透镜(SPWL),利用几何光学方法分析了它的光学特性,得出其传输矩阵,并进行了特殊的结构设计.介绍了实际制备这种透镜的工艺过程,并给出了光纤输出光束经1/4节距的自聚焦平板波导透镜之后输出的近场和远场光斑图,测试结果表明自聚焦平板波导透镜输出近场光斑在x-z平面内束宽为1 153.3μm,与根据传输矩阵计算得出的束宽1 153.2 μm相符;最后介绍了自聚焦平板波导透镜的三种应用实例:LD阵列和光纤的耦合、SOA与单模光纤的耦合、光功率分束器和直波导阵列波导光栅. 相似文献
3.
4.
Si基槽型光波导的传输特性分析和传输损耗的测量 总被引:3,自引:3,他引:0
对Si基槽型(slot)光波导的传输特性进行了研究。 采用三 维时域有限差分(3D-FDTD)法研究了芯层中的光功率与波导槽型宽度及Si条带宽度之间的关 系,结果显示,槽型光波导具有很好的光功率约束效率,可以达到30%以上; 分析了光功率的变化规律及其优化,综合考虑光功率和光功率密度确定波导结构参数,实现 最佳光功率分 布,横向光功率分布沿x轴方向具有很好的约束效果,沿y轴方向呈现高斯分布;分析了底部Si薄层对光 功率的影响,100nm的底部Si薄层使得芯层的光功率下降50%,减小 底部Si薄层厚度有利于光功率约束效 率的提高;采用电子束刻写(EBL)技术和等离子刻蚀(ICP)技术制备了Si基槽型光波导,实验 研究了其传输损耗,结果显示,槽型光波导具有较低的传输损耗,达到13.5dB/cm。 相似文献
5.
为了实现横截面尺寸为50 m50 m的聚硅氧烷聚合物光波导的耦合转向问题,设计了一种表面覆盖高折射率包层的多层蚀刻光栅耦合器。首先,分析了影响聚合物波导光栅耦合器耦合效率的结构因素;然后,采用在光栅表面蚀刻高折射率层的方法,提高了聚合物波导光栅耦合器的耦合效率;接着,对不同的周期(范围:100~4 000 nm)和不同的蚀刻深度(范围:0~50 000 nm)进行排列组合,形成不同的光栅结构,基于时域有限差分法编写程序,遍历所有情况,得到不同光栅结构下的光场情况以及其耦合效率,找到使耦合效率最大的周期以及蚀刻深度。最后,设计了多层蚀刻的光栅耦合器,进一步提高耦合效率。当蚀刻深度为5 000 nm,光栅周期为2 600 nm时,带高折射率层的聚硅氧烷聚合物光波导均匀光栅耦合器的耦合效率达到最大,为17.2%。采用多层蚀刻的方式,对结构进行优化,其耦合效率能达到37.4%。为聚硅氧烷聚合物光波导在光互连中的实际应用提供了理论依据。 相似文献
6.
仿真和实验研究了含槽型(slot)光波导的反馈波导型微环谐振器的特性,将槽型光波导集成到Si基微环谐振器中,丰富Si基光波导的功能,为新型光电子器件的实现提供途径。通过锥形波导结构实现从传统波导到槽型波导的模式转换,减小传输损耗,采用时域有限差分法(FDTD)研究了光功率的分布和模式转换过程。结果显示,光功率逐渐转移到锥形结构两侧的槽型波导中并最终形成槽型波导中的传输模式,通过优化锥形结构能实现较高的模式转换效率,可以达到90%以上。采用电子束刻写技术和等离子刻蚀技术制备了反馈波导型槽型微环谐振器。实验显示,锥形波导能够实现模式的转换,光传输过程良好。通过在槽型波导中填充电光聚合物来改变槽型光波导的折射率,测量结果显示,传输谱谐振峰发生了明显移动,移动幅度达到5.6nm,器件具备很好的可调谐性。 相似文献
7.
8.
单模光纤与条形波导的耦合封装技术 总被引:1,自引:0,他引:1
本文对单模光纤与条形波导的耦合封装技术进行了评述。使用改进后的“倒装”耦合技术进行了耦合实验,完成了单模光纤耦合 Ti:LiNbO_3波导相位调制器的封装,达到了光纤/器件(2厘米长波导)/光纤总插入损耗小于5dB。同时,阐述了耦合技术的发展方向。 相似文献
9.
10.
由于金属固有的欧姆损耗,表面等离子体波导通常具有较大的传输损耗。基于此,提出了一种全介质反槽波导结构,该波导可以同时实现亚波长模式局域性和理论上无损耗的传输,归一化模式面积可以达到3.4×10-2。另外,为了实现该小尺寸反槽波导与输入/输出光纤的高效耦合,提出了一种高效的耦合方案,耦合效率可以达到92.7%,在y和z方向上1 dB损耗的耦合偏差均约为2 μm。 相似文献
11.
The coupling between the guided modes and between guided and radiation modes of two parallel slab waveguides forming a directional coupler in order is computed to determine the radiation losses introduced by the coupling grating. The problem is solved in two stages. First, the guided modes for each waveguide are computed separately and the radiation modes are only determined for the more complicated of the two waveguides, the one that is nearer to the grating. Modifications caused by the presence of the opposite waveguide are then taken into account by computing first-order correction terms. For a practical example of slab waveguides defined in GaInAsP, the authors find that the radiation losses per power exchange length remain below 0.02 dB for a rectangular grating depth of 0.01 μm 相似文献
12.
A study of fiber-to-fiber losses in waveguide grating routers 总被引:2,自引:0,他引:2
Most of the waveguide grating router's loss comes from fiber coupling and star coupler. Our three-dimensional (3-D) models quantifies both losses. In addition, we study how various waveguide parameters affect the value and nonuniformity of this loss. Our optimization yields a design where the total fiber-to-fiber insertion loss can be reduced to 0.535 dB 相似文献
13.
L.G. de Peralta A.A. Bernussi S. Frisbie R. Gale H. Temkin 《Photonics Technology Letters, IEEE》2003,15(10):1398-1400
A high-performance reflective arrayed waveguide grating multiplexer/demultiplexer designed for compatibility with silicon integrated circuit processing is described. The grating, folded by a flat reflecting surface, can be printed in a single-exposure field of a photolithographic stepper. Advanced plasma assisted deposition is used to prepare waveguides with very low loss and minimum birefringence. Multiplexers with 40 channels separated by 100 GHz show intrinsic insertion losses of -2.4 dB, channel uniformity less than 0.6 dB, and very low polarization dependent wavelength shift of 0.012 nm. 相似文献
14.
Grating coupling between vertically integrated waveguides via supermode was discussed and demonstrated. Two thin-film waveguides with grating couplers were stacked on a substrate. A guided wave in one waveguide is converted by a grating coupler to a supermode propagating contradirectionally, and then converted by another grating coupler to a guided wave in the other waveguide. The coupling shows high wavelength selectivity, and the wavelength-division add/drop multiplexing function can be combined. A demonstrator was designed and fabricated. Theoretically predicted coupling efficiency was almost 100% with wavelength selectivity of 2 nm, while the experimentally obtained value was 40% in the efficiency and 1 nm in the selectivity 相似文献
15.
16.
Mizuno T. Kitoh T. Saida T. Inoue Y. Itoh M. Shibata T. Hibino Y. Hida Y. 《Electronics letters》2001,37(24):1452-1454
A low coupling loss of 0.5 dB/point between 1.5%-Δ silica-based waveguides and a singlemode fibre has been achieved by employing a simple laterally tapered waveguide with a narrow core width. By applying this structure to an arrayed waveguide grating multiplexer, the insertion loss was decreased from 4.9 to 2.6 dB 相似文献
17.
A multilevel grating coupler based on silicon-on-insulator (SOI) material structure is proposed to realize the coupling between waveguide and waveguide or waveguide and fiber. This coupler is compatible with the current fabrication facilities for complementary metal oxide semiconductor (CMOS) technology with vertical coupling. This structure can realize coupling when the beams with transverse electric (TE) polarization and transverse magnetic (TM) polarization are incident at the same time. The influences of the grating coupler parameters including wavelength, the thickness of waveguide layer, the thickness of SiO2 layer and the number of steps on the TE mode and TM mode coupling efficiencies are discussed. Theory researches and simulation results indicate that the wavelength range is from 1533 nm to 1580 nm when the TE mode and TM mode coupling efficiencies are both more than 40% as the grating period is 0.99 μm. The coupling efficiencies of the incident TE and TM modes are 49.9% and 49.5% at the wavelength of 1565 nm, respectively, and the difference between them is only 0.4%. 相似文献
18.
Directional couplers are successfully fabricated on acrylic substrates using polymers synthesised from deuterated methacrylate and deuterated fluoromethacrylate monomers. The excess loss of a 50 mm long coupler is about 0.7 dB including waveguide and fibre coupling losses. A novel method is proposed for tuning the coupling ratio. By bending the coupler, high precision control of within 1% is attained without optical polarisation dependence.<> 相似文献
19.
Stacked polymeric multimode waveguide arrays for two-dimensional optical interconnects 总被引:1,自引:0,他引:1
Joon-Sung Kim Jang-Joo Kim 《Lightwave Technology, Journal of》2004,22(3):840-844
Two-dimensional (2-D) polymeric multimode waveguide arrays with two reflection-mirrors have been fabricated for optical interconnects between 2-D arrayed vertical-cavity surface-emitting lasers and detectors. Contact printing lithography was adopted for simple and low-cost process using ultraviolet-curable epoxy-based polymers. Fabricated waveguides were diced of the same size and stacked one by one with lateral positional errors less than /spl plusmn/20 /spl mu/m. Two kinds of mirrors were fabricated: single-reflection mirror and double-reflection mirror. Double-reflected mirrors resulted in lower losses with 1.2 dB than single reflected mirrors with 2.1 dB. The average insertion losses of 16-channel arrayed waveguides with two single-reflection mirrors and with two double-reflection-mirrors were measured to be 6.1 and 4.4 dB for 6-cm-long waveguides at a wavelength of 830 nm, respectively. The crosstalk between the waveguides was less than -25 dB. The characteristics of the waveguide arrays are good enough for applications to optical interconnects. 相似文献