【作者】 李雪春；

【导师】 林金桐；

【作者基本信息】 北京邮电大学 ， 物理电子学， 2009， 博士

【摘要】 微集成光子器件是光子芯片的重要组成部分。光子集成是指在一个普通的平面衬底上制作和集成许多光子元件。这些元件包括分光器、光栅、耦合器、偏振器、干涉仪、光源和检测器等。在这个基础上制作成一个功能块,许多这样的功能块集成起来可以实现更复杂的功能,如光通讯系统、仪器和传感器等。它的传输媒介是光子,所以具有高速、大容量、抗电磁干扰性强等优点。本论文讨论的是两种微集成光子器件:光子晶体滤波器和微流体光波导传感器。本论文提出的基于耦合模式理论和传输矩阵法的理论模型可以快速的找出各个参数对光子晶体滤波器和光栅性能的影响,从而可以对它们的性能进行优化。本论文还提出两种技术来抑制光子晶体滤波器的旁瓣,啁啾技术和优化级联技术,理论上这两种技术的边模抑制比能达到30dB。与切趾技术相比这两种方法简单有效的抑制了旁瓣,并且在控制滤波器带宽和陡峭边沿上有很大的灵活性,在工艺上易于实现。微光子器件和微流体器件合成做成微流体光器件,一方面可以集成生物化学传感器,待测物通过流体运送到高灵敏度微光子器件进行分析,另一方面微流体控制微光子器件,使微光子器件可控、可调、可重组。本论文首先对微流体光波导的传输及损耗特性进行了测量与讨论,接着设计了基于微流体光波导的传输型传感器和吸收型传感器。基于倏逝波传输特性的传感器,尺寸大小为3cm×3cm,探测折射率灵敏度为△S/△C=275μm² L/mol。基于样品吸收特性的传感器,尺寸大小为3.5cm×3cm,rhodamin 6G的探测极限浓度是5×10^-9mol/L（0.5ng/mL）,Mathylene blue的探测极限是5×10^-8mol/L（0.16ng/mL）。与固体波导传感器相比,由于流体既是样品的承载者,又是光学测量的主体,使用上更加灵活和方便,而且液体波导传感器的灵敏度相同但尺寸减小。传输型和吸收性传感器结构上是一样的。传输型可用于高浓度样品测量,吸收型适用于低浓度样品测量。同一个芯片可以同时满足不同的测量需要,这是固液型传感器做不到的。基于微流体光波导的双Mach-Zenhder干涉仪可以用来探测粒子所在位置,进而控制粒子传输方向,进行粒子分类,这是一种高灵敏度的粒子分类仪器。更多还原

【Abstract】 Integrated photonic device is an important part of photonics circuits. ’Integrated photonics’ means several photonic components fabricated and integrated on a planar substrate. These components include beam splitters, gratings, couplers, polarisers, interferometers, sources and detectors, and others. In turn, these can then be used as buiding blocks to fabricate more complex planar devices which can perform a wide range of functions with applications in optical communication systems and sensors.The advantanges of the photonic device are the high speed, large capacity, low loss and so on because the propogation media is photonics. In this thesis two integrated device is discussed, photonic crystal filter and micro liquid/liquid waveguide.This thesis presents the theoretical model of the side-coupled photonic crystal filter and the gratings. Numerical verification shows a good agreement between the theoretic method and the finite-difference time-domain simulation, but the theoretic method does not involve the time-consuming computation. The theoretical method also presents a better physical image for choosing the critical parameters. Based on the theoretic model, two optimization methods (chirp and cascading) are proposed to deeply suppress the sidelobes, the sidelobe surpression ratio is 30dB. They also show more flexibility in controlling the bandwidth and steepness of the roll-off in the filter. Comparing to apodized technique, it is easy to fabricate.The potential applications of the micro integrated photonic devices and microfluidic systems are mainly twofold. In the context of integrated biochemical sensing, fluids can be used to carry substances to be analysed through highly sensitive microphotonic circuits. Conversely, microfluids can be exploited to control microphotonic devices, making them tunable, reconfigurable and adaptive. In the thesis the optical properties such as the propogation and the loss of the liquid/liquid waveguide were measured and discussed. Two liquid/liquid waveguide sensors were proposed, transmission sensor and absorption sensor. The size of the transmission sensor is 3cm×3cm. The sensitivity is△S/△C=275μm~2 L/mol. The size of the absorption sensor is 3.5cm×3cm. The limitation of detection is 0.5 ng/mL for rhodamin 6G and 0.16 ng/mL for Mathylene blue. Campared with the solid/liquid sensor the liquid/liquid senor has the advantage of flexible and easy for use. The liquid sensor has small size when its sensitivity is the same as the solid/liquid sensor. The two sensos have the same structure. The transmision sensor can be used for the high concentration sample detection and the absorption can be used for the low concentration. It is impossible for traditional solid/liquid waveguide senor to use the same circiut to satisfy the different needs. The twin Mach-Zenhder interferometer based on the liquid/liquid waveguide can be used to detect the position of the paticles for the particles sorting. This particle sorting device is high sensitivity.更多还原