【作者】 张颖颖；

【导师】 李振华；

【作者基本信息】 南京理工大学 ， 光学工程， 2009， 博士

【摘要】 SPR传感技术因其灵敏度高、待测物无需纯化、可实现免标记、实时和无损伤检测等独特优点,在临床诊断、生化制药及环境检测等方面有广泛的应用前景。本论文以提高SPR传感的灵敏度和分辨率及拓展SPR技术的应用范围为目的,在理论和实验上对SPR耦合结构、探测光束主要参数对SPR传感器性能的影响及SPR技术在吸收介质测量方面的应用等作了较为系统深入的研究,论文取得的创新性成果主要有：对比分析了四种棱镜耦合结构(传统SPR结构、长程SPR结构、耦合等离子体波导共振结构和波导耦合SPR结构)SPR传感器的性能及适用性条件,通过详实的数值模拟,重点分析了在角度调制、波长调制和强度调制方式下,不同结构SPR传感器直接检测样品折射率变化和检测传感层折射率或厚度变化时的灵敏度、分辨率及线性测量范围,对SPR传感器耦合结构的优化设计有重要参考价值。探讨了探测光束准直度、谱线宽度和偏振度对SPR传感器的影响,发现三者中探测光束准直度的影响最为显著。准直度的下降不仅使SPR传感器分辨率降低,还会造成基于强度检测的SPR成像传感器各探测点间反射率和灵敏度差异。上述结果对SPR传感器中光源的设计有一定的指导意义。提出了利用SPR相位差法测量吸收介质复折射率的方法。在分析了生物组织的光学特性后,利用该方法实验测量得到了Intralipid溶液(仿生物组织)和兔血的复折射率,模拟得到实部和虚部的测量不确定度均可达10-4量级。此外,以吸收介质复折射率的lorentz模型为基础,研究了SPR技术在检测吸收介质样品折射率实部和虚部变化方面的应用。这些研究拓宽了SPR技术的应用范围,并为混浊介质复折射率的高精度测量提供了一个可能的方法。研究了二维亚波长周期SPR结构的传输特性并将其应用于折射率传感,分析了各参数对透射增强峰的影响并给出了理论解释和定性分析。结果表明,在二维周期金属膜结构上,既有由周期引起的表面等离子体共振,还有其它共振模式；通过调整结构可以得到比棱镜耦合SPR的共振峰细锐得多的共振峰,应用于折射率传感时可以获得更高的抗噪声性能和分辨率。该研究可应用于新型SPR传感器的设计制作。更多还原

【Abstract】 The technology of Surface Plasmon Resonance (SPR) has wide prospect in clinical diagnosis, biochemical pharmaceutics, environmental detection, etc, as a result of its particular advantages of high sensitivity, non-purification of sample, and the detection with free label, real time as well as non-traumatic. In order to enhance the sensitivity and resolution of the SPR sensor, and extend the application of SPR technology, the systemic and profound researches are implemented theoretically and experimentally on the SPR coupling configuration, the influence of the probe beam’s parameters on the performance of the SPR sensor and the application of SPR technology on the absorbing medium detection and so on. In a word, the innovative achievements are listed as follows:By comparison, the performance and applicability of four prism coupling configurations (including the conventional SPR, Longe Range SPR, Coupled Plasmon Waveguide Resonance and Waveguide Coupled SPR) of SPR sensors are analyzed. Based on the numerical simulation, the sensitivity, resolution and linearity measurement range of the different SPR sensors are researched in detail under the angle, wavelength and intensity modulations respectively, when they are used to detect the sample’s refractive index variation and the sensing layer’s variation of the refractive index or thickness. As expected, all the results are valuable for the configuration design of SPR sensors.The influence of the probe beam’s collimated degree, breadth of spectrum line and polarization degree on the SPR sensor is discussed. The results show that the collimated degree is the most notable factor among the three parameters. Concretely speaking, the drop of the collimated degree will not only decrease the resolution but also induce the non-uniformity of reflectivity and sensitivity differences among the probe spots for the imaging SPR sensor based on the intensity detection. Therefore, these results can supply some significant guidance for the source design of the SPR sensor.A new method which determines the complex refractive index of absorbing medium with SPR phase detection is proposed. The complex refractive index of Intralipid solutions (imitating the biological tissues) and leporine blood are experimentally measured by the new proposed method, on the basis of analyzing the biological tissues’optical characters. The simulated results indicate that the measurement uncertainty of the complex refractive index’s real and imaginary parts can reach to 10-4. Furthermore, the application of SPR technology in detecting the variation of complex refractive index for absorbing medium is studied based on the Lorentz model. Hence, these researches extend the application range of SPR technology, and provide a possible method that has high-precision in the measurement of the complex refractive index for turbid medium.The transmission character of a two-dimensional and sub-wavelength SPR structure which will be applied to the refractive index sensor is studied. The effect of each parameter on the transmission peak is analyzed and explained theoretically. The results manifest that not only SPR which caused by the period but also the other resonance modes exist in the two-dimensional periodic metal film at the same time. As a matter of fact, a resonant peak which is much sharper than that of the prism coupling SPR can be obtained by adjusting the periodic configuration. Based on which a sensor with better noise-resistance and higher resolving power can be gained. In short, this study can be used in the design of novel SPR sensors.更多还原