共查询到16条相似文献,搜索用时 406 毫秒
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以拓宽Ag膜波长调制型表面等离子体共振(SPR)传感器的工作波长区间,将TiO2膜沉积于Ag膜表面制成Ag-TiO2复合薄膜.利用数值计算方法对不同厚度Ag膜和As-TiO2复合膜波长调制型SPR光谱特性进行仿真研究.仿真结果表明:共振吸收峰显著依赖于Ag膜厚度;当保持Ag-TiO2复合膜厚度60 nm时,复合薄膜SPR波长随TiO2厚度的增大而向长波长方向移动,发现红移;与60 nm厚Ag膜共振波长相比,12 nm厚TiO2与48 rnm厚Ag组成的复合膜共振波长红移超过200 nm. 相似文献
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光纤表面等离子体共振(Surface plasmon resonance,SPR)传感器是一种将光纤纤芯作为激发SPR效应基体的新型传感器.本篇论文基于LabVIEW搭建虚拟仿真设计平台,依照材料参数与组件结构做理论计算,可即时改变尺寸及材料参数,了解SPR组件参数对感测效果的影响,找到最佳参数.以PMMA塑料光纤虚拟仿真结果显示,镀银薄膜40nm于光纤研磨表面上,能够制造出一个较佳的光纤SPR传感器;最后,以不同折射率的待测物进行仿真计算,得到共振波长与折射率关系. 相似文献
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针对光纤SPR(表面等离子体共振)传感器制作工艺复杂的问题,提出了一种光纤先固定后部分镀膜的SPR传感芯片的制作方法.依据电磁场和射线理论,分析并讨论了此种波长调制部分镀膜SPR传感芯片的工作原理,采用MEMS制作工艺对探测光纤进行封装固定以后,再对光纤进行部分镀膜,其结构简单,工艺性好,易于实现批量化.最后,搭建了一套基、于波长检测的光纤SPR测试系统对其进行测试.实验结果表明:在折射率范围为1.33~1.36时,共振波长同折射率具有良好的线性关系,光谱仪分辨率为0.1 m时,其分辨率可达到3×10-5折射率单位. 相似文献
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表面等离子体共振 (SPR)技术是一种简单直接的传感技术 ,SPR对金属表面附近的折射率的变化极为敏感 ,利用这一性质 ,表面等离子体共振传感器已成为生物传感器研究领域的热点。现提出一种电光调制波导型SPR模型 ,模拟计算表明该模型在不损害灵敏度的条件下 ,扩大了探测的动态范围。 相似文献
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针对棱镜激励银膜SPR传感器灵敏度虽然较金膜结构高,但易被氧化、稳定性较差的缺点,提出一种棱镜耦合激励银膜-石墨烯-介质-石墨烯-银膜复合膜对称结构的SPR传感器,增加石墨烯膜层,解决银膜SPR传感器易氧化导致稳定性下降问题,采用角度调制的方法对SPR传感结构进行了性能参数分析,研究了金属材质、石墨烯以及检测介质的厚度对传感性能的影响。结果表明,银膜相比金膜,具有更好的共振效果,灵敏度较高,通过调节检测介质的厚度,可以改变角度的调节范围,实现了传感器的可调性,对称传感结构可以产生双共振峰SPR曲线,为分布式传感提供了可供参考的依据,石墨烯优化并提高了传感器的稳定性和检测灵敏度。 相似文献
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介绍了一种采用不规则四边形棱镜设计的小型化表面等离子体共振(SPR)生物传感器。棱镜结构与已有的TI Spreeta传感器类似,但是在尺寸、光学性能等方面做了较大优化。新研制的SPR传感器在光学检测精度和系统集成性等方面也有了很大提高。在光路设计中,采用波长为630 nm的宽光束红光LED作为光源,5 000像素点线阵CCD作为光电检测器,光学检测效果要大大优于TI Spreeta波长为830 nm的近红外光源和128像素点的线阵硅光二极管。在光路优化的同时,系统集成了流动控制模块、信号采集处理模块,形成了一个可实现生物大分子相互作用分析的集成小型化SPR检测装置。利用空气、水及乙醇等进行的SPR实验表明:该装置能够对单一样本进行精确检测,共振角的检测精度高达0.01°,且检测结果线性度高,稳定性好,单一样本的检测偏差小于0.5%。 相似文献
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高折射率铌酸锂(LiNbO3)(2.202)为棱镜耦合激发的角度调制型表面等离子共振传感器,利用反射率公式优化单层银膜、金膜和双层银/金膜传感器薄膜的厚度,分别计算了优化厚度的传感器在检测样品折射率为1.330时的共振角、灵敏度、峰值半宽度(FWHM)和品质因数(FOM),理论计算表明:双层金属薄膜,随着金膜厚度的增加,传感器灵敏度增加,但峰值半宽度增加,品质因数下降.综合考虑,选择银/金(41/5)优化组合,传感器品质因数为优化的单层金膜(47 nm)传感器品质因数的2倍以上,另外,与常用的BK7玻璃棱镜耦合相比,LiNbO3棱镜耦合具有较大的样品动态检测范围.优化厚度的传感器实验检测糖水浓度表明:糖水浓度与共振角为线性比例关系. 相似文献
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Fu E Ramsey SA Chen J Chinowsky TM Wiley B Xia Y Yager P 《Sensors and actuators. B, Chemical》2007,123(1):606-613
We describe the resonance wavelength-dependent signal of absorptive particles in surface plasmon resonance (SPR)-based detection using both modeling and experimental results. The particles, gold nanocages, have a significant absorption cross-section in the nearinfrared (NIR), resulting in a wavelength-dependent refractive index as measured by SPR. The SPR signal due to the nanocages varies by 4-fold over resonance wavelengths from 650 nm to 950 nm. The greatest SPR signal occurs at the longest resonance wavelengths; its magnitude is due to the inherent increase in sensitivity of SPR on gold with increasing wavelength and the optical absorption properties of the nanocages. 相似文献
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To improve the sensitivity of a single-mode D-type optical fiber sensor, we selected a D-type optical fiber sensor with 4 mm long and 4 μm core thickness made of a single-mode fiber, a Au-coating on the sensor with a thickness range of 15–32 nm, a light wavelength of 632.8 nm, and an incident angle of 86.5–89.5° for different refractive index (1.33–1.40) sensing. These simulations are based on the surface plasmon resonance (SPR) theory using the phase method which shows that the sensitivity is proportional to the refractive index, Au film thickness and lower incident angle on the sensing interface. The sensitivity is higher than 4000 (degree/RIU), and the resolution is better than 2.5 × 10−6(RIU) as the minimum phase variation is 0.01°. This device is used to detect the refractive index or gas or liquid concentration in real-time. The proposed sensor is small, simple, inexpensive, and provides an in vivo test. 相似文献
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Influence of ions on the surface plasmon resonance spectrum of a fiber optic refractive index sensor
Sachin K. SrivastavaAuthor VitaeBanshi D. GuptaAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(2):559-562
Surface plasmon resonance (SPR) spectra of a fiber optic SPR probe coated with thin gold layer have been studied experimentally for four ionic (NaCl, KCl, Na2SO4 and MgCl2) and two non-ionic (sucrose and urea) liquid samples of different refractive indices. For the same value of refractive index, the response curves for ionic and non-ionic liquid samples have been found to differ, implying the influence of ions on the resonance wavelength of the SPR spectrum. It is observed that the resonance wavelength, for a given refractive index of the liquid, is higher for ionic sample than that in the case of non-ionic one. This extra increase in resonance wavelength is attributed to the interaction of ions with the free electrons of the metal film. The study finds importance in situations where ions get generated during the processes. In such studies, the effect of ions on SPR spectrum must be incorporated otherwise the SPR spectrum may get wrongly interpreted. 相似文献
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Surface plasmon resonance (SPR) sensor schemes based on silicon (Si) and chalcogenide glass are evaluated and compared for chemical as well as gas detection in a wide range of infrared (IR) wavelengths. The plasmonic characteristics in IR are critically dependent on the dispersive behavior of the coupling substrate material. The performance of sensor has been evaluated in terms of its intrinsic sensitivity (IS) that includes the FWHM and angular shift of SPR curve for a given change in refractive index of sensing medium. Both these materials are potential candidates for opening up new routes for detection in near- and mid-IR due to their strong dispersion capabilities as compared to normal silica-based glass. The IS of chalcogenide glass-based SPR sensor is found to be larger than Si-based one for a broad wavelength range of 700–2500 nm indicating that chalcogenide glass-based probe provides more sensitive as well as accurate sensing procedure than Si-based probe. Further, for both glasses, the single probe can be used for both aqueous as well as gaseous sensing. Furthermore, for both glasses, it is found that the values of IS are much larger for gaseous sensing in comparison to liquid sensing. 相似文献
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A way to improve the angular sensitivity of surface plasmon resonance (SPR) biosensor by tuning the resonance position to a higher incident angle region using a lower refractive index glass prism is described in this paper. A novel effective 3-layer (E3L) model is described to transform a multiple layer biosensor configuration in context of SPR condition. The E3L model supports the use of a low refractive index prism for biosensing. The performance of the sensor in immunosensing is checked for two glass prisms of different refractive index materials. The experimental results showed an enhancement in the amount of resonance angle shift of the immunosensor for the lower refractive index glass prism. 相似文献