High-sensitivity refractive index sensors based on Fano resonance in the plasmonic system of splitting ring cavity-coupled MIM waveguide with tooth cavity

Herein, a nanosensor structure is proposed, which comprises metal-insulator-metal (MIM) waveguide with stub and circular ring cavity with a stub (CRCS). The phenomenon of Fano resonance appears in the transmission spectrum, which is formed by interaction between the narrowband mode of CRCS and broadband mode of stub on bus waveguide. The influence of geometric asymmetry on mode splitting of Fano resonance was discussed. The mode splitting of Fano resonance can vastly improve figure of merit (FOM) with a sight decrease of sensitivity. The best performance of the refractive-index nanosensor is attained, which is 1420 nm/RIU with a high FOM of 76.76. Additionally, the application of designed structure on temperature sensing was investigated, which has sensitivity of 0.8 nm/°C. The proposed structure also possesses potential applications on other on-chip nanosensors.

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Strain, torsion and refractive index sensors based on helical long period fibre grating inscribed in small-core fibre for structural condition monitoring

Advances in Structural Engineering ◽

10.1177/1369433221992485 ◽

2021 ◽

Vol 24 (6) ◽

pp. 1248-1255

Author(s):

Cailing Fu ◽

Yi-Qing Ni ◽

Tong Sun ◽

Yiping Wang ◽

Siqi Ding ◽

...

Keyword(s):

Refractive Index ◽

High Sensitivity ◽

Single Mode ◽

Structural Condition ◽

Core Diameter ◽

Small Core ◽

Long Period ◽

Sensing Applications ◽

Core Fibre ◽

Refractive Index Sensors

This study is intended to develop long period fibre grating sensors for potential applications in environmental and durability monitoring of coastal structures. High-quality helical long period fibre gratings (HLPFGs) are inscribed in different types of small-core single mode fibre (SMF) by use of hydrogen-oxygen flame heating technique. A detailed investigation of the effect of core diameter on their transmission spectrum and optimum length of the HLPFG has been pursued. A longer length is required to achieve the same coupling attenuation in a smaller-core SMF than that of a larger-core fibre. The strain, torsion and refractive index (RI) properties of the HLPFG is investigated experimentally to develop a high-sensitivity sensor. The experimental results show that the strain sensitivity could be enhanced by means of employing a larger-core diameter SMF. Moreover, the HLFPGs are also sensitive to the torsion and external RI. Hence, such HLFPGs have great potential for sensing applications.

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Improved Refractive Index-Sensing Performance of Multimode Fano-Resonance-Based Metal-Insulator-Metal Nanostructures

Nanomaterials ◽

10.3390/nano11082097 ◽

2021 ◽

Vol 11 (8) ◽

pp. 2097

Author(s):

Yuan-Fong Chou Chau ◽

Chung-Ting Chou Chao ◽

Siti Zubaidah Binti Haji Jumat ◽

Muhammad Raziq Rahimi Kooh ◽

Roshan Thotagamuge ◽

...

Keyword(s):

Refractive Index ◽

Plasmon Resonance ◽

Fano Resonance ◽

High Sensitivity ◽

Metal Nanostructures ◽

Refractive Index Sensor ◽

Metal Insulator ◽

Wide Range ◽

Metal Insulator Metal ◽

Mode 2

This work proposed a multiple mode Fano resonance-based refractive index sensor with high sensitivity that is a rarely investigated structure. The designed device consists of a metal–insulator–metal (MIM) waveguide with two rectangular stubs side-coupled with an elliptical resonator embedded with an air path in the resonator and several metal defects set in the bus waveguide. We systematically studied three types of sensor structures employing the finite element method. Results show that the surface plasmon mode’s splitting is affected by the geometry of the sensor. We found that the transmittance dips and peaks can dramatically change by adding the dual air stubs, and the light–matter interaction can effectively enhance by embedding an air path in the resonator and the metal defects in the bus waveguide. The double air stubs and an air path contribute to the cavity plasmon resonance, and the metal defects facilitate the gap plasmon resonance in the proposed plasmonic sensor, resulting in remarkable characteristics compared with those of plasmonic sensors. The high sensitivity of 2600 nm/RIU and 1200 nm/RIU can simultaneously achieve in mode 1 and mode 2 of the proposed type 3 structure, which considerably raises the sensitivity by 216.67% for mode 1 and 133.33% for mode 2 compared to its regular counterpart, i.e., type 2 structure. The designed sensing structure can detect the material’s refractive index in a wide range of gas, liquids, and biomaterials (e.g., hemoglobin concentration).

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Enhancing the sensitivity of a standard plasmonic MIM square ring resonator by incorporating the Nano-dots in the cavity

Photonics Letters of Poland ◽

10.4302/plp.v12i1.902 ◽

2020 ◽

Vol 12 (1) ◽

pp. 1 ◽

Cited By ~ 3

Author(s):

Muhammad Ali ALI Butt ◽

Nikolay Kazanskiy

Keyword(s):

Refractive Index ◽

Fano Resonance ◽

Ring Resonator ◽

Plasmonic Waveguide ◽

Metal Insulator ◽

Refractive Index Sensing ◽

Sensing Applications ◽

Resonator Design ◽

Metal Insulator Metal ◽

Mim Waveguide

We studied the metal-insulator-metal square ring resonator design incorporated with nano-dots that serve to squeeze the surface plasmon wave in the cavity of the ring. The E-field enhances at the boundaries of the nano-dots providing a strong interaction of light with the surrounding medium. As a result, the sensitivity of the resonator is highly enhanced compared to the standard ring resonator design. The best sensitivity of 907 nm/RIU is obtained by placing seven nano-dots of radius 4 nm in all four sides of the ring with a period (ᴧ)= 3r. The proposed design will find applications in biomedical science as highly refractive index sensors. Full Text: PDF References:Z. Han, S. I. Bozhevolnyi. "Radiation guiding with surface plasmon polaritons", Rep. Prog. Phys. 76, 016402 (2013). [CrossRef]N.L. Kazanskiy, S.N. Khonina, M.A. Butt. "Plasmonic sensors based on Metal-insulator-metal waveguides for refractive index sensing applications: A brief review", Physica E 117, 113798 (2020). [CrossRef]D.K. Gramotnev, S.I. Bozhevolnyi. "Plasmonics beyond the diffraction limit", Nat. Photonics 4, 83 (2010). [CrossRef]A.N.Taheri, H. Kaatuzian. "Design and simulation of a nanoscale electro-plasmonic 1 × 2 switch based on asymmetric metal–insulator–metal stub filters", Applied Optics 53, 28 (2014). [CrossRef]P. Neutens, L. Lagae, G. Borghs, P. V. Dorpe. "Plasmon filters and resonators in metal-insulator-metal waveguides", Optics Express 20, 4 (2012). [CrossRef]M.A. Butt, S.N. Khonina, N. L. Kazanskiy. "Metal-insulator-metal nano square ring resonator for gas sensing applications", Waves in Random and complex media [CrossRef]M.A.Butt, S.N.Khonina, N.L.Kazanskiy. "Hybrid plasmonic waveguide-assisted Metal–Insulator–Metal ring resonator for refractive index sensing", Journal of Modern Optics 65, 1135 (2018). [CrossRef]M.A.Butt, S.N. Khonina, N.L. Kazanskiy, "Highly sensitive refractive index sensor based on hybrid plasmonic waveguide microring resonator", Waves in Random and complex media [CrossRef]Y. Fang, M. Sun. "Nanoplasmonic waveguides: towards applications in integrated nanophotonic circuits", Light:Science & Applications 4, e294 (2015). [CrossRef]H. Lu, G.X. Wang, X.M. Liu. "Manipulation of light in MIM plasmonic waveguide systems", Chin Sci Bull [CrossRef]J.N. Anker et al. "Biosensing with plasmonic nanosensors", Nature Materials 7, 442 (2008). [CrossRef]M.A.Butt, S.N. Khonina, N.L. Kazanskiy. Journal of Modern Optics 66, 1038 (2019).[CrossRef]Z.-D. Zhang, H.-Y. Wang, Z.-Y. Zhang. "Fano Resonance in a Gear-Shaped Nanocavity of the Metal–Insulator–Metal Waveguide", Plasmonics 8,797 (2013) [CrossRef]Y. Yu, J. Si, Y. Ning, M. Sun, X. Deng. Opt. Lett. 42, 187 (2017) [CrossRef]B.H.Zhang, L-L. Wang, H-J. Li et al. "Two kinds of double Fano resonances induced by an asymmetric MIM waveguide structure", J. Opt. 18,065001 (2016) [CrossRef]X. Zhao, Z. Zhang, S. Yan. "Tunable Fano Resonance in Asymmetric MIM Waveguide Structure", Sensors 17, 1494 (2017) [CrossRef]J. Zhou et al. "Transmission and refractive index sensing based on Fano resonance in MIM waveguide-coupled trapezoid cavity", AIP Advances 7, 015020 (2017) [CrossRef]V. Perumal, U. Hashim. "Advances in biosensors: Principle, architecture and applications", J. Appl. Biomed. 12, 1 (2014)[CrossRef]H.Gai, J. Wang , Q. Tian, "Modified Debye model parameters of metals applicable for broadband calculations", Appl. Opt. 46 (12), 2229 (2007) [CrossRef]

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High-sensitivity complex refractive index sensing based on Fano resonance in the subwavelength grating waveguide micro-ring resonator

Optics Express ◽

10.1364/oe.25.020911 ◽

2017 ◽

Vol 25 (17) ◽

pp. 20911 ◽

Cited By ~ 30

Author(s):

Zhengrui Tu ◽

Dingshan Gao ◽

Meiling Zhang ◽

Daming Zhang

Keyword(s):

Refractive Index ◽

Fano Resonance ◽

Ring Resonator ◽

Complex Refractive Index ◽

High Sensitivity ◽

Subwavelength Grating ◽

Refractive Index Sensing

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Sensing Features of the Fano Resonance in an MIM Waveguide Coupled with an Elliptical Ring Resonant Cavity

Applied Sciences ◽

10.3390/app10155096 ◽

2020 ◽

Vol 10 (15) ◽

pp. 5096

Author(s):

Hao Su ◽

Shubin Yan ◽

Xiaoyu Yang ◽

Jing Guo ◽

Jinxi Wang ◽

...

Keyword(s):

Refractive Index ◽

Optical Sensors ◽

Fano Resonance ◽

Resonant Cavity ◽

Refractive Index Sensor ◽

Geometrical Parameters ◽

Elliptical Ring ◽

Metal Insulator Metal ◽

Promising Application ◽

Mim Waveguide

In this article, a novel refractive index sensor composed of a metal–insulator–metal (MIM) waveguide with two rectangular stubs coupled with an elliptical ring resonator is proposed, the geometric parameters of which are controlled at a few hundreds of nanometer size. The transmission feature of the structure was studied by the finite element method based on electronic design automation (EDA) software COMSOL Multiphysics 5.4 (Stockholm, Sweden). The rectangular stub resonator can be thought of as a Fabry–Perot (FP) cavity, which can facilitate the Fano resonance. The simulation results reveal that the structure has a symmetric Lorentzian resonance, as well as an ultrasharp and asymmetrical Fano resonance. By adjusting the geometrical parameters, the sensitivity and figure of merit (FOM) of the structure can be optimized flexibly. After adjustments and optimization, the maximum sensitivity can reach up to 1550 nm/RIU (nanometer/Refractive Index Unit) and its FOM is 43.05. This structure presented in this article also has a promising application in highly integrated medical optical sensors to detect the concentration of hemoglobin and monitor body health.

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Fano Resonance in an Asymmetric MIM Waveguide Structure and Its Application in a Refractive Index Nanosensor

Sensors ◽

10.3390/s19040791 ◽

2019 ◽

Vol 19 (4) ◽

pp. 791 ◽

Cited By ~ 14

Author(s):

Mengmeng Wang ◽

Meng Zhang ◽

Yifei Wang ◽

Ruijuan Zhao ◽

Shubin Yan

Keyword(s):

Refractive Index ◽

Integrated Circuits ◽

Fano Resonance ◽

Structural Parameters ◽

High Sensitivity ◽

Split Ring Resonator ◽

Peak Position ◽

Optical Integrated Circuits ◽

Metal Insulator Metal ◽

Calculation Results

Herein, the design for a tunable plasmonic refractive index nanosensor is presented. The sensor is composed of a metal–insulator–metal waveguide with a baffle and a circular split-ring resonator cavity. Analysis of transmission characteristics of the sensor structures was performed using the finite element method, and the influence of the structure parameters on the sensing characteristics of the sensor is studied in detail. The calculation results show that the structure can realize dual Fano resonance, and the structural parameters of the sensor have different effects on Fano resonance. The peak position and the line shape of the resonance can be adjusted by altering the sensitive parameters. The maximum value of structural sensitivity was found to be 1114.3 nm/RIU, with a figure of merit of 55.71. The results indicate that the proposed structure can be applied to optical integrated circuits, particularly in high sensitivity nanosensors.

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