基于光波导环腔结构的生物传感器研究

发布时间：2018-05-30 07:58

本文选题：微环谐振腔 + 传感器　；参考：《广西大学》2015年硕士论文

【摘要】：光波导环腔传感器具有灵敏度高、抗电磁干扰性强、微型化等优点成为了目前热门研究的传感器件之一。其利用介质中传播的倏逝场来感应环境折射率的变化,从而进行生物探测。本文基于强度探测和波长探测方法,提出了两种新型传感器件,研究了其器件结构和传感特性,给出了优化设计方案,在优化设计下,提出的新型传感器取得了优良的性能。完成的主要研究工作如下：首先针对微型化、集成化、稳定性好、灵敏度高的生物传感探测,设计了一种新型的反馈式跑道型光学微环传感器,该传感器主要由U型反馈波导、跑道谐振腔和敏感环组成。采用传输矩阵方法推导了该传感器的归一化输出光强公式,数值分析了传输损耗因子、自耦合因子和敏感环尺寸等对传感灵敏度的影响性质。根据分析结果对结构参数进行了优化,优化结构不仅可以输出尖锐陡峭的非对称法诺谐振光强谱线,还具有较高的法诺谐振光谱斜率,能更好的增强传感灵敏度。在信噪比为30dB的测量系统中,优化的反馈式跑道型光学微环传感器的探测极限可以达到4.48×10名单位折射率。其次针对宽谱的波长探测型生物传感应用,设计了一种基于马赫-曾德干涉(Mach-Zehnder Interference,MZI)结构的可产生游标效应的双微环谐振腔传感器。其主要由两个3dB耦合器、两组双直波导、一个敏感环和一个参考环组成。采用耦合模理论推导了该传感器的归一化输出光强公式,分析了其光强输出谱线性质。仿真分析表明,该传感器可输出具有较大振幅的主谐振峰光强谱线,其主谐振峰可呈数字式移动,当被探测物的有效折射率变化为探测极限的整数倍时,主谐振峰的位置以步长λm成倍漂移。在优化设计下,该传感结构可获得6.732×10-5RIU的较低探测极限,灵敏度达到3.730×104nm/RIU,比传统的双直波导单微环谐振腔灵敏度高近52倍；当使用带宽为310nm的光源时,可以探测的物质有效折射率的变化范围为0.0083,具有探测动态范围宽、探测极限低和灵敏度不易受自由光谱范围影响等优点。
[Abstract]:Optical waveguide ring cavity sensor has become one of the most popular sensor devices because of its high sensitivity, strong resistance to electromagnetic interference and miniaturization. It makes use of evanescent field propagating in medium to induce the change of environmental refractive index, so as to carry out biological detection. Based on the methods of intensity detection and wavelength detection, two new sensor devices are proposed in this paper. The structure and sensing characteristics of the sensor are studied, and the optimal design scheme is given. Under the optimal design, the new sensor has achieved excellent performance. The main research work is as follows: firstly, a new feedback runway optical microloop sensor is designed for the biosensor with miniaturization, integration, good stability and high sensitivity. The sensor is mainly composed of U-shaped feedback waveguide. Runway resonator and sensitive ring. The normalized output intensity formula of the sensor is derived by using the transfer matrix method. The effects of the transmission loss factor, the self-coupling factor and the size of the sensitive ring on the sensitivity of the sensor are numerically analyzed. According to the analysis results, the structure parameters are optimized. The optimized structure can not only output sharp and steep asymmetric Farno resonance intensity spectrum line, but also have a higher Fano resonance spectral slope, which can enhance the sensing sensitivity better. In the measurement system with 30dB signal to noise ratio, the detection limit of the optimized feedback runway optical microloop sensor can reach 4.48 脳 10 unit refractive index. Secondly, a dual-microring resonator sensor based on Mach-Zehnder interference MZI (Mach-Zehnder Interferenceer MZI) structure is designed for wide-spectrum wavelength detection biosensor applications. It consists of two 3dB couplers, two groups of double straight waveguides, a sensitive ring and a reference ring. The normalized output light intensity formula of the sensor is derived by using the coupling mode theory, and the properties of the light intensity output line of the sensor are analyzed. The simulation results show that the sensor can output the main resonant peak intensity line with large amplitude, and the main resonant peak can be moved digitally. When the effective refractive index of the detected object changes to an integer multiple of the detection limit, The position of the main resonance peak drifts exponentially with the step size 位 m. Under the optimized design, the sensing structure can obtain a lower detection limit of 6.732 脳 10-5RIU, with a sensitivity of 3.730 脳 10 ~ 4 nm / r, which is nearly 52 times higher than that of the conventional double-straight waveguide single-microloop resonator. When the light source with bandwidth of 310nm is used, The range of effective refractive index of detectable material is 0.0083, which has the advantages of wide detection dynamic range, low detection limit and low sensitivity influenced by free spectrum range.
【学位授予单位】：广西大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN252;TP212

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