【作者】 张超；

【导师】 黄翊东；

【作者基本信息】 清华大学 ， 电子科学与技术， 2009， 硕士

【摘要】 慢光波导是一种可以控制光波传输群速度的波导结构,由于光群速度的减慢等效于波矢空间光子态密度的增加,慢光技术在光信号处理、非线性光电子器件以及光子集成技术中有着重要的应用。本论文以实现可集成的慢光波导为目标,研究利用SOI平板光子晶体波导中的异常色散效应实现慢光。就结构设计、制备工艺、测试方法、慢光延时应用等关键问题,从理论和实验上展开了研究。论文的成果如下:优化设计了SOI平板光子晶体慢光波导的结构,研究了SOI平板光子晶体波导的制备工艺流程,确立空气桥结构的制备工艺,成功研制出高质量的平板光子晶体波导。设计了条形接续波导的宽度,降低了拉锥光纤与条形波导的耦合损耗;设计了条形波导和光子晶体波导之间的接口,降低了慢光波段条形波导与光子晶体波导的耦合损耗,当群速度vg=c/50时,该耦合损耗小于3dB。研究了光纤与波导的耦合测试方法,编写了测试平台自动控制软件,大大缩短耦合测试时间。测试出光子禁带和缺陷模式,论证了缺陷模式导光。利用光纤马赫曾德尔干涉仪的方法,测量出了光子晶体波导中慢光的群速度,达到真空光速的1/80。研究了光子晶体慢光波导的时域延时特性,利用慢光对调制在光上的电信号进行延时。理论分析计算了调制信号的延时和畸变。实验实现了10GHz微波调制信号25ps的可调延时。更多还原

【Abstract】 Slow light waveguide can control the group velocity of light. The reduction of light speed equals to the increase of photon density in wave-vector space. Slow light technology has important applications in light signal process, nonlinear optoelectronic devices and photonic integration technology.Aiming at integratable slow light waveguide, slow light based on novel dispersion character of photonic crystal slab waveguide has been studied in this paper. Structure design, fabrication process, measurement method, and slow light true time delay were studied theoretically and experimentally. The achievements are as follows:Optimized the waveguide structure, studied the fabrication process of SOI photonic crystal waveguide, found the fabrication process of air-bridge, high quality photonic crystal slab waveguide is fabricated.Designed the width of stripe waveguide to increase coupling efficiency between tapered fiber and stripe waveguide. Designed the interface between stripe waveguide and photonic crystal waveguide to increase coupling efficiency in slow light wavelength region (loss<3dB, when vg=c/50).Studied the measurement method, programmed the automatic control software of measurement system and greatly reduced the measurement time. Photonic bandgap and defect mode are measured and demonstrated.Group index of slow light is measured by fiber Mach-Zehnder interferometer, showing the light speed is less than c/80. The optical true time delay character of photonic crystal waveguide is studied. A 25ps tunable delay is experimentally demonstrated.更多还原