scholarly journals Resonant Grating without a Planar Waveguide Layer as a Refractive Index Sensor

Sensors ◽  
2019 ◽  
Vol 19 (13) ◽  
pp. 3003 ◽  
Author(s):  
Sivan Isaacs ◽  
Ansar Hajoj ◽  
Mohammad Abutoama ◽  
Alexander Kozlovsky ◽  
Erez Golan ◽  
...  

Dielectric grating-based sensors are usually based on the guided mode resonance (GMR) obtained using a thin planar waveguide layer (PWL) adjacent to a thin subwavelength grating layer. In this work, we present a detailed investigation of thick subwavelength dielectric grating structures that exhibit reflection resonances above a certain thickness without the need for the waveguide layer, showing great potential for applications in biosensing and tunable filtering. Analytic and numerical results are thoroughly discussed, as well as an experimental demonstration of the structure as a chemical sensor in the SWIR (short wave infrared) spectral range (1200–1800 nm). In comparison to the GMR structure with PWL, the thick grating structure has several unique properties: (i) It gives higher sensitivity when the spaces are filled, with the analyte peaking at certain space values due to an increase in the interaction volume between the analyte and the evanescent optical field between the grating lines; (ii) the TM (transverse magnetic) resonance, in certain cases, provides a better figure of merit; (iii) the sensitivity increases as the grating height increases; (iv) the prediction of the resonance locations based on the effective medium approximation does not give satisfactory results when the grating height is larger than a certain value, and the invalidity becomes more severe as the period increases; (v) a sudden increase in the Q-factor of the resonance occurs at a specific height value accompanied by the high local field enhancement (~103) characteristic of a nano-antenna type pattern. Rigorous numerical simulations of the field distribution are presented to explain the different observed phenomena.

2020 ◽  
Vol 10 (4) ◽  
pp. 353-363
Author(s):  
Lanting Ji ◽  
Shuqing Yang ◽  
Rongna Shi ◽  
Yujie Fu ◽  
Juan Su ◽  
...  

Abstract A waveguide coupled surface plasmon sensor for detection of liquid with high refractive index (RI) is designed based on polymer materials. The effects of variation of the thickness of the Au film, polymethyl methacrylate (PMMA) buffer, and waveguide layer on the sensing performance of the waveguide are comprehensively investigated by using the finite difference method. Numerical simulations show that a thinner gold film gives rise to a more sensitive structure, while the variation of the thickness of the PMMA buffer and waveguide layer has a little effect on the sensitivity. For liquid with high RI, the sensitivity of the sensor increases significantly. When RI of liquid to be measured increases from 1.45 to 1.52, the sensitivity is as high as 4518.14nm/RIU, and a high figure of merit of 114.07 is obtained. The waveguide coupled surface plasmon RI sensor shows potential applications in the fields of environment, industry, and agriculture sensing with the merits of compact size, low cost, and high integration density.


2005 ◽  
Author(s):  
Hisao Kikuta ◽  
Koichi Fujita ◽  
Akio Mizutani ◽  
Hiroshi Toyota ◽  
Koichi Iwata

2017 ◽  
Vol 5 (4) ◽  
Author(s):  
Anil Yuksel ◽  
Edward T. Yu ◽  
Jayathi Murthy ◽  
Michael Cullinan

Surface plasmon polaritons associated with light-nanoparticle interactions can result in dramatic enhancement of electromagnetic fields near and in the gaps between the particles, which can have a large effect on the sintering of these nanoparticles. For example, the plasmonic field enhancement within nanoparticle assemblies is affected by the particle size, spacing, interlayer distance, and light source properties. Computational analysis of plasmonic effects in three-dimensional (3D) nanoparticle packings are presented herein using 532 nm plane wave light. This analysis provides insight into the particle interactions both within and between adjacent layers for multilayer nanoparticle packings. Electric field enhancements up to 400-fold for transverse magnetic (TM) or X-polarized light and 26-fold for transverse electric (TE) or Y-polarized light are observed. It is observed that the thermo-optical properties of the nanoparticle packings change nonlinearly between 0 and 10 nm gap spacing due to the strong and nonlocal near-field interaction between the particles for TM polarized light, but this relationship is linear for TE polarized light. These studies help provide a foundation for understanding micro/nanoscale heating and heat transport for Cu nanoparticle packings under 532 nm light under different polarization for the photonic sintering of nanoparticle assemblies.


2020 ◽  
Vol 10 (9) ◽  
pp. 3033 ◽  
Author(s):  
Guofeng Li ◽  
Junbo Yang ◽  
Zhaojian Zhang ◽  
Kui Wen ◽  
Yuyu Tao ◽  
...  

The realization of the electromagnetically induced transparency (EIT) effect based on guided-mode resonance (GMR) has attracted a lot of attention. However, achieving the multispectral EIT effect in this way has not been studied. Here, we numerically realize a double EIT-ike effect with extremely high Q factors based on a GMR system with the double-bar dielectric grating structure, and the Q factors can reach 35,104 and 24,423, respectively. Moreover, the resonance wavelengths of the two EIT peaks can be flexibly controlled by changing the corresponding structural parameters. The figure of merit (FOM) of the dual-mode refractive index sensor based on this system can reach 571.88 and 587.42, respectively. Our work provides a novel method to achieve double EIT-like effects, which can be applied to the dual mode sensor, dual channel slow light and so on.


Author(s):  
Sergey Sarkisov ◽  
Michael Curley ◽  
Courtney Boykin ◽  
Darnell Diggs ◽  
James Grote ◽  
...  

Sensors ◽  
2018 ◽  
Vol 18 (12) ◽  
pp. 4489 ◽  
Author(s):  
Chunlian Cen ◽  
Hang Lin ◽  
Jing Huang ◽  
Cuiping Liang ◽  
Xifang Chen ◽  
...  

In the present study, we design a tunable plasmonic refractive index sensor with nanoring-strip graphene arrays. The calculations prove that the nanoring-strip have two transmission dips. By changing the strip length L of the present structure, we find that the nanoring-strip graphene arrays have a wide range of resonances (resonance wavelength increases from 17.73 μm to 28.15 μm). When changing the sensing medium refractive index nmed, the sensitivity of mode A and B can reach 2.97 μm/RIU and 5.20 μm/RIU. By changing the doping level ng, we notice that the transmission characteristics can be tuned flexibly. Finally, the proposed sensor also shows good angle tolerance for both transverse magnetic (TM) and transverse electric (TE) polarizations. The proposed nanoring-strip graphene arrays along with the numerical results could open a new avenue to realize various tunable plasmon devices and have a great application prospect in biosensing, detection, and imaging.


2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Junming Chen ◽  
Haopeng Huang ◽  
Yibing Zhang ◽  
Yonglu Wang ◽  
Fanyu Kong ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document