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1.
内置调制层型光纤表面等离子体波共振传感器研究 总被引:2,自引:1,他引:1
研究了一种基于内置调制层结构的光纤表面等离子体波共振(SPR)传感器。通过在金膜与纤芯的内侧增覆具有不同厚度和属性的光学透明薄膜作为内调制层,构成了性能独特的光电复合薄膜,起到调节倏逝波矢量和金膜表面等离子体振荡波矢量的双重作用,进而控制共振效应,为调节灵敏度提供依据。采用时域有限差分方法对内置调制层结构光纤SPR共振激励模型属性进行数值仿真。在此基础上,研制了用于液体折射率测量的内置调制层型光纤SPR传感探针。实验结果表明,该传感器在1.335~1.392折射率范围内,随着待测液体折射率的增大,SPR共振光谱向长波方向偏移,且灵敏度达到2263.1nm/RIU,与基于纤芯-金膜-环境介质三层结构的常规光纤SPR传感器相比提高一倍,能够更好地满足环境折射率检测的需求。 相似文献
2.
Mohammad Reza Soheilifar 《Optical and Quantum Electronics》2018,50(12):442
The optical absorber with Fano response is valuable for various applications such as solar cells or optical sensors. In this paper, we have modeled an optical plasmonic metamaterial absorber which contains a broken cross as an elementary cell along with four rectangular loads to improve the absorbance and achieve a Fano response within a wide bandwidth at 190–245 THz (25%). The bandwidth of the proposed structure is more than conventional metamaterial absorbers. The prototype absorber has a remarkable enhancement in the electric field in comparison with the simple cross model and the reflection value has reduced to ??47 dB. The parametric studies show how the gap capacitance controls the bandwidth, resonance frequency and the reflection value of the absorber, therefore we can consider this technique as a way to enhance the metamaterial absorber’s bandwidth. The proposed structure can be used as an optical refractive index sensor while the Fano line-shape provides a higher figure of merit (FOM) compared with many others. For this structure, the FOM has obtained as 10,660. The Finite Integration Technique with Perfect Boundary Approximation used for the simulation. 相似文献
3.
基于表面等离子体共振原理的空芯光纤传感器 总被引:2,自引:0,他引:2
设计了一种基于表面等离子体共振原理,使用空芯光纤作为光波导、外表面镀金属膜的光学材料圆柱体作为探头的新型折射率传感器。通过建立光学模型进行分析,在理论上推导出了这种传感器的传输光谱损耗公式,并针对该传感器在不同的光纤长度、探头材料、检测物质折射率等参数设置下的检测性能进行了分析,获得了各种参数对其性能的影响。由于该传感器可针对不同折射率的检测物质灵活地更换合适探头材料,相对于传统的表面等离子体共振光纤传感器,在易用性和性价比等方面具有更好的应用价值。 相似文献
4.
Sensitivity enhancement in TE mode nonlinear planar optical waveguide sensor with metamaterial layer
The dispersion equation of the TE mode nonlinear planar optical waveguide with metamaterial layer was derived, and the sensitivity of the waveguide sensor was analyzed. The influences of structural parameters on the sensitivity of the waveguide sensor were investigated. We verify that the waveguide sensor with metamaterial layer can dramatically enhance the sensitivity compared with other waveguide sensors. 相似文献
5.
High Sensitivity Transmission-Type SPR Sensor by Using Metallic--Dielectric Mixed Gratings
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We theoretically investigate transmission-type SPR sensors with novel metallic-dielectric mixed gratings by rig- orous coupled-wave analysis (RCWA), compared to the conventional dielectric gratings based structure. It is found that the transmittance efficiency and the full width at half-maximum (FWHM) of the transmission curve can be modulated by increasing or decreasing the metallic part. Therefore, appropriate proportion of metal part will induce enhancement factor of sensor merit. Furthermore, this novel structure will also bring enhancement of resonant angle shift, which can be explained by plasmonie interpretation based on a surface limited increase of interaction area and excitation of localized surface plasmons (LSPs). The proposed configuration has a wide range of potential applications not only as sensor but also other optical devices. 相似文献
6.
Kamrun Nahar Shushama Md. Masud Rana Reefat Inum Md. Biplob Hossain 《Optical and Quantum Electronics》2017,49(11):381
In this paper, a highly sensitive surface plasmon resonance biosensor is presented using angular interrogation. Due to low sensitivity of conventional biosensor, graphene/two-dimensional transition metal are used in surface plasmon resonance biosensor to improve the sensitivity. Here, we propose a seven layer model of biosensor which shows by incorporating silicon layer in addition of transition metal dichalcogenides MoS2 and graphene, the sensitivity of the proposed SPR biosensor can be greatly enhanced than the conventional gold film SPR sensors. It is observed that the highest sensitivity can be obtained by optimizing the structure with 8 nm thickness of silicon layer, one layer of MoS2 and one layer of graphene. The highest sensitivity of our proposed sensor is 210°/RIU. 相似文献
7.
A surface plasmon resonance(SPR) sensor with a high-order absentee layer on the top of metallic film is proposed.The performance of the SPR sensor with NaCl, MgO, TiO_2 or AlAs high-order absentee layer is analyzed theoretically. The results indicate that the sensitivity and the full width at half maximum of those SPR sensors decrease with the increasing of the order of absentee layer, but the variation of the figure of merit(FOM) depends on the refractive index of absentee layer.By improving the order of absentee layer with high-refractive-index, the FOM of the SPR sensor can be enhanced. The maximum value of FOM for the SPR sensor with high-order TiO_2(or AlAs) absentee layer is 1.059%(or 2.587%) higher than the one with one-order absentee layer. It is believed the proposed SPR sensor with high-order absentee layer will be helpful for developing the high-performance SPR sensors. 相似文献
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9.
《中国物理 B》2018,(11)
We investigate a kind of spectral splitting effect in a plasmonic multilayer system, which consists of stacked Al_2 O_3 and SiO_2 layers, a thin metal film, and a dielectric prism substrate. The results illustrate that an obvious peak appears in the center of the surface plasmon resonance(SPR)-induced reflection spectral dip in the structure with the SiO_2/Al_2 O_3/SiO_2 layers. This spectral splitting response can be regarded as an electromagnetically induced transparency(EIT) like effect,which is attributed to the coupling and interference between the SPR on the metal film and guided-mode resonance(GMR)in the Al_2 O_3 layer. The theoretical calculations agree well with the numerical simulations. It is also found that the reflection spectrum will be further split by the introduction of another Al_2 O_3 layer into the multilayer structure. The reintroduced GMR in the Al_2 O_3 layer changes the coupling and interference process between the SPR and GMR field, giving rise to the generation of ultra-narrow reflection dip. Especially, the spectral splitting can facilitate the realization of plasmonic sensors with ultra-high figure of merit(583), which is about 5 times larger than that of traditional SPR sensors. These results will provide a new avenue to the light field manipulation and optical functionalities, especially biochemical and environmental sensing. 相似文献
10.
Natalia Díaz HerreraÓscar Esteban María-Cruz NavarreteAgustín González-Cano Elena Benito-PeñaGuillermo Orellana 《Optics and Lasers in Engineering》2011,49(8):1065-1068
We present the results of a chemical attack on the optical fiber surface previous to the deposition of the double layer (metal plus dielectric) in Double-layer uniform-waist tapered fibers (DLUWTs) used for the development of SPR sensors. It is shown how this simple chemical treatment increases the roughness of the surface and permits improvement of the stability of the deposits and the general performance of the sensors. The obtained devices are robust and very compact, their sensitivity is good and repeatability of the measurements is remarkably increased. The procedure can be useful for any fiber-optic sensor. 相似文献
11.
提出并研制了基于光纤SPR传感探针的新型湿敏传感器。首先研究了光纤SPR传感探针对环境湿度变化的敏感特性,在此基础上提出在光纤SPR传感探针表面增覆不同厚度且具有水分子吸附功能的PVA薄膜来实现环境相对湿度的监测。研究结果表明,增覆双层PVA薄膜的光纤SPR传感探针在高湿区具有较好监测效果,其共振强度对应的相对湿度测量灵敏度达到1.59%/%RH,较光纤SPR探针呈现显著提高。而增覆单层PVA薄膜的光纤SPR传感探针在高湿区共振波长对应的相对湿度监测灵敏度达到2.411nm/%RH。此外所提出的新型光纤SPR湿敏探针在PVA薄膜失效后经过特殊工艺处理仍可重复镀膜使用。 相似文献
12.
Zhong Yin Xiao Zi Hua Wang 《International Journal of Infrared and Millimeter Waves》2006,27(3):443-454
In this paper, the reflection and transmission coefficients of multi-layer dielectric and metamaterial media are derived by
transmission-line method. Then, it is applied to double periodic photonic crystal structure, which is composed of two thin
dielectric layers sandwiched by two thin metamaterial layers. The results show the structure has a large passband and a monotonous
symmetric rising band edges compared with that for a conventional photonic crystal structure. If a defect layer is introduced,
the localized modes appear. Furthermore, the number of transmission peaks in the photonic crystal structure can be tuned by
changing the thickness of the defect in the structure. This photonic crystal may find application to broadband reflectors
and the multi-wavelength narrow band optical filters. 相似文献
13.
We propose theoretically two optical sensor structures based on Fabry–Perot resonator and fringes of equal thickness structure. Different from the conventional slab waveguide sensors in which the sample interacts with the evanescent field in the cladding layer, the proposed sensors contain the sample in the core layer. The first proposed sensor comprises a piezoelectric material as a substrate with the driving potential difference as the sensing probe for refractive index changes of the sample. The second sensor comprises fringes of equal thickness structure with the number of fringes per unit length is the probe for changes in the index of the sample. The calculations reveal that the proposed sensors have high sensitivity to changes in the refractive index of the sample. 相似文献
14.
提出了一种基于反向表面等离子体共振原理,由Ge_(20)Ga_5Sb_(10)S_(65)-钯-石墨烯分子-生物分子四层结构构成的新型生物传感器。当生物分子之间发生相互作用时,引起生物分子层折射率的变化,从而导致反向表面等离子体共振角的偏移。在此基础上,根据传输矩阵法推导了传感器的输出光谱,重点讨论了本文提出的传感器与传统传感器相比,在灵敏度、分辨率、动态检测范围以及检测信号信噪比方面取得的进展。另外,通过对比研究,深入分析了辅助介质层石墨烯厚度对传感器性能的影响。最后,利用近红外光作为提出的传感器的入射光,分析了在近红外区域传感器性能的改善。研究结果表明:单层石墨烯分子使传感器性能达到最佳;反向表面等离子共振峰强度约为入射光强的80%~90%,使传感器的输出信号具有较大的信噪比;在可见光区域,当入射光波长为632.8nm时,提出的反向表面等离子共振生物传感器的分辨率是基于SiO_2棱镜耦合反向表面等离子共振生物传感器的1.9倍,是传统表面等离子共振生物传感器的3.5倍,提出的传感器的动态检测范围约是现有传感器的2倍;利用Ge_(20)Ga_5Sb_(10)S_(65)棱镜可使反向表面等离子共振生物传感器检测光波长由可见光区域扩展到近红外区域,当入射光为1 000nm时,传感器的分辨率是可见光区域的3~4倍。该研究对基于反向表面等离子体共振原理生物传感器的实现与发展具有重要意义。 相似文献
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16.
A surface plasmon resonance (SPR) sensing system based on the optical cavity enhanced detection tech-nique is experimentally demonstrated. A fiber-optic laser cavity is built with a SPR sensor inside. By measuring the laser output power when the cavity is biased near the threshold point, the sensitivity, defined as the dependence of the output optical intensity on the sample variations, can be increased by about one order of magnitude compared to that of the SPR sensor alone under the intensity interrogation scheme. This could facilitate ultra-high sensitivity SPR biosensing applications. Further system miniaturization is possible by using integrated optical components and waveguide SPR sensors. 相似文献
17.
表面等离子体共振(SPR)传感系统有角度谱、光谱、强度、相位等解调方式,其中光谱型的(SPR)传感系统因可以使用光纤导光,将传感部分独立出来,可进行远距离传感和现场检测,并能有效缩小系统的体积。对称光波导型(SOW)SPR因金属膜层两边的折射率完全相同,表面等离子体波传播距离更长,穿透深度更深,比传统的SPR系统具有更高的灵敏度和分辨率。对对称波导型(SOW)SPR进行光谱解调研究,以MgF2-Au-MgF2结构的SOW-SPR为传感单元,同时以光纤输出的卤素灯为光源, 搭建了一套光谱解调的SOW-SPR检测系统,以不同浓度的葡萄糖溶液对系统折射率分辨率进行测量,得到2.8×10-7 RIU的分辨率。为SOW-SPR系统小型化、现场检测以及远距离探测提出一种可能实现的手段,具有很好的应用前景。 相似文献
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19.
Bridging the terahertz near-field and far-field observations of liquid crystal based metamaterial absorbers
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Metamaterial-based absorbers play a significant role in applications ranging from energy harvesting and thermal emitters to sensors and imaging devices.The middle dielectric layer of conventional metamaterial absorbers has always been solid.Researchers could not detect the near field distribution in this layer or utilize it effectively.Here,we use anisotropic liquid crystal as the dielectric layer to realize electrically fast tunable terahertz metamaterial absorbers.We demonstrate strong,position-dependent terahertz near-field enhancement with sub-wavelength resolution inside the metamaterial absorber.We measure the terahertz far-field absorption as the driving voltage increases.By combining experimental results with liquid crystal simulations,we verify the near-field distribution in the middle layer indirectly and bridge the nearfield and far-field observations.Our work opens new opportunities for creating high-performance,fast,tunable,terahertz metamaterial devices that can be applied in biological imaging and sensing. 相似文献
20.
Long Zheng Xia Zhang Xiaomin Ren Jing Gao Lei Shi Xiaolong Liu Qi Wang Yongqing Huang 《Optics & Laser Technology》2011,43(5):960-964
Surface plasmon resonance sensors based on Ag-metalized nanolayer in microstructured optical fibers are theoretically analyzed by using finite element method (FEM). In our simulations we use Drude-Lorentz model to describe the metal dielectric constant. The numerical results show that the sensitivity of Ag-metalized SPR sensor could reach 1167 nm/RIU and corresponding resolution is 8.57×10−5 RIU. Compared to conventional Au-metalized SPR sensors the performance of our device is obviously better. 相似文献