Dual-channel narrowband polarization absorber with high field enhancement and refractive index sensitivity based on a nanorod array

The localized surface plasmon resonance of homo-dimer nanostructures is studied using FDTD simulations. The calculated LSPR wavelength of Au, Ag and Al nanosphere forming a homo-dimer configuration is compared and the results reveal a larger LSPR shift in Ag and Al homo-dimer than in Au homo-dimer. Taking the sensitivity of LSPR shape to the size and interparticle spacing of nanoparticle along with a surrounding refractive index, parameters like refractive index sensitivity have been determined. The spherical homo-dimer over the whole range of particle size, studied here shows the index sensitivity order as Ag>Al>Au. Hence, the use of plasmonic material towards the refractive index sensing applications is useful in this order. The average refractive index sensitivities of Ag, Al and Au are 287.09 nm/RIU, 210.21 nm/RIU and 192.47 nm/RIU in DUV-Visible-NIR region. Apart from LSPR shift, the highly confined near-field intensity enhancement of homo-dimer nanostructures for SERS has also been studied. The interacting homo-dimer nanoparticles reveals intensity enhancements in the junction. Comparing the field enhancement for Au, Ag and Al homo-dimer nanostructure 10^8-10^9 have been theoretically predicted in DUV-UV-visible region which can be used to strongly enhance the Raman scattering of molecules.

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Refractive index sensitivity characteristic of long-period grating in holey fiber with dual-channel measuring method

Optik ◽

10.1016/j.ijleo.2013.11.051 ◽

2014 ◽

Vol 125 (11) ◽

pp. 2612-2615 ◽

Cited By ~ 1

Author(s):

Shouhua Guan ◽

Qingxu Yu

Keyword(s):

Refractive Index ◽

Measuring Method ◽

Long Period Grating ◽

Refractive Index Sensitivity ◽

Holey Fiber ◽

Long Period ◽

Dual Channel ◽

Index Sensitivity ◽

Sensitivity Characteristic

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Improved Refractive Index Sensitivity Utilizing Long-Period Gratings with Periodic Corrugations on Cladding

Journal of Sensors ◽

10.1155/2012/483471 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5 ◽

Cited By ~ 12

Author(s):

Anthony Lim ◽

Wen Bin Ji ◽

Swee Chuan Tjin

Keyword(s):

Refractive Index ◽

Cost Effective ◽

Experimental Results ◽

Refractive Index Sensitivity ◽

Long Period ◽

Specimen Collection ◽

Long Period Gratings ◽

Highly Sensitive ◽

Index Sensitivity

A new structure of Long-Period Gratings (LPGs) sensor is introduced as a sensitive ambient RI sensor. This structure consists of creating periodic corrugations on the cladding of the LPG. The experimental results show that this LPG structure has good performances in terms of linearity and sensitivity and serves as a highly sensitive and cost-effective sensor. It also has the advantage of portability as the corrugation can also serve as the reservoir for the specimen collection to be tested.

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The local surface plasmon resonance property and refractive index sensitivity of metal elliptical nano-ring arrays

AIP Advances ◽

10.1063/1.4901910 ◽

2014 ◽

Vol 4 (11) ◽

pp. 117115 ◽

Cited By ~ 1

Author(s):

Weihua Lin ◽

Qian Wang ◽

Qiuze Li ◽

Anhua Dong

Keyword(s):

Refractive Index ◽

Surface Plasmon Resonance ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Local Surface ◽

Resonance Property ◽

Refractive Index Sensitivity ◽

Local Surface Plasmon Resonance ◽

Index Sensitivity

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Improve the Hole Size-dependent Refractive Index Sensitivity of Au-Ag Nanocages by Tuning the Alloy Composition

10.21203/rs.3.rs-482206/v1 ◽

2021 ◽

Author(s):

Jianjun LI ◽

Qiu-Xiang Qin ◽

Guo-Jun Weng ◽

Jian Zhu ◽

Jun-Wu Zhao

Keyword(s):

Dielectric Constant ◽

Refractive Index ◽

Electric Field ◽

Alloy Composition ◽

Geometric Parameters ◽

Sensitivity Factor ◽

Hole Size ◽

Refractive Index Sensitivity ◽

Electric Field Direction ◽

Index Sensitivity

Abstract In this study, the nanoboxes is converted into Au-Ag alloy nanocages by increasing the hole size. Discrete dipole approximation (DDA) is used to study the extinction spectrum and the refractive index sensing characteristics of Au-Ag alloy nanocages with different geometric parameters. With the increase of Au component, the local surface plasmon resonance (LSPR) peak shows approximately linear redshift and the sensitivity factor shows approximately linear decrease. The refractive index sensitivity can be effectively controlled by the Au-Ag ratio at large hole size because the hole and cavity surfaces distribute more environmental dielectric components. Therefore, increasing the hole size and decreasing the Au-Ag ratio can improve the refractive index sensitivity. To explain the effect of alloy composition on the LSPR characteristics and the refractive index sensitivity, the local electric field distributions with different geometric parameters are plotted. We find that the electric field direction on the hole and cavity surfaces are controlled by the Au-Ag ratio and environmental dielectric constant. Moreover, the field vector on the hole and cavity surfaces are formed by the superposition of the incident field, the electric field generated by the oscillating electrons on the outer surface, and the polarized field in the environmental dielectric constant.

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