Effects of Morphology of Nanodots on Localized Surface Plasmon Resonance Property

2014 ◽  
Vol 8 (1) ◽  
pp. 74-82 ◽  
Author(s):  
Truong Duc Phuc ◽  
◽  
Masahiko Yoshino ◽  
Akinori Yamanaka ◽  
Takatoki Yamamoto ◽  
...  

In this paper, authors report the effects of process parameters of thermal annealing method on the morphologyand Localized Surface Plasmon Resonance (LSPR) property of gold nanodots. Results show that the nanodots aggregated on a quartz glass substrate are large and sparse, while the nanodots aggregated on a silicon substrate are small and dense. The peak of the absorbance spectra is shifted to a longer wavelength and becomes broader when the gold film is thicker. The absorbance intensity increases with the increase in the gold film thickness. Increase the annealing temperature and/or the annealing time result in a blue shift of the absorbance peak and a decrease in the peak intensity. It is found that the variation in the absorbance peak wavelength and peak intensity closely correlates to the variation in the average circularity of the nanodots. This result suggests that the LSPR of nanodots can be tuned by controlling themorphology, specifically the circularity, of the nanodots.

NANO ◽  
2015 ◽  
Vol 10 (08) ◽  
pp. 1550117
Author(s):  
Chao Liu ◽  
Jingwei Lv ◽  
Famei Wang ◽  
Qiang Liu ◽  
Haiwei Mu ◽  
...  

Multilayered nanoshells have attracted much attention due to their unique optical, electronic and magnetic properties. In this work, numerical calculation using discrete dipole approximation (DDA) is conducted to investigate the quad-layered metal nanoshell consisting of a particle with a dielectric silica (SiO2) core, inner cadium sulfide (CdS) shell, middle indium tin oxide (ITO) shell and outer metal silver (Ag) shell. The phenomenon is interpreted by plasmon hybridization theory and the Ag–ITO–CdS–SiO2 multilayered nanoshells are studied by extinction spectra of localized surface plasmon resonance. The variation in the spectrum peak with nanoparticle thickness and refractive index of the surrounding medium is derived. The electric field enhancement contour around the nanoparticles under illumination is analyzed at the plasmon resonance wavelength. The [Formula: see text], [Formula: see text], and [Formula: see text] modes red-shift with the refractive index of the surrounding medium and increase in the layer thickness causes either blue-shift or red-shift as shown by the extinction spectra. The mechanism of the red-shift or blue-shift is discussed. The [Formula: see text] mode blue-shifts and furthermore, the [Formula: see text] and [Formula: see text] modes of the Ag coated multilayered nanostructure are noticeable by comparing the extinction efficiency spectra of the Au–ITO–CdS–SiO2 and Ag–ITO–CdS–SiO2 multilayered nanoshells.


2008 ◽  
Vol 8 (7) ◽  
pp. 3369-3378 ◽  
Author(s):  
Xiaodong Zhou ◽  
Selven Virasawmy ◽  
Wolfgang Knoll ◽  
Kai Yu Liu ◽  
Man Siu Tse ◽  
...  

The gold nanostructures fabricated on a substrate yield localized surface plasmon resonance. We describe the fabrication and characterization of nanocrescents on a silicon substrate, which are fabricated by depositing a gold film at an oblique angle through nanosphere lithography. Following the etching of the gold perpendicular to the substrate and the removal of the nanospheres by dissolution, nanocrescents with fine nanostructures are generated. By varying the deposition angle of the gold film from 0° to 72°, nanorings, 2D and 3D nanocrescents can be obtained. During the nanocrescent fabrication, we also compared the deposition angle difference between the e-beam and thermal evaporators for oblique depositions of the gold. The 3D nanocrescents fabricated in our experiments are expected to have improved sensitivity in localized surface plasmon resonance measurements when compared to the previously reported 2D nanocrescents, which enable broader biosensor applications. Simulations of the profiles of these 3D nanocrescents using solid geometry show good consistency with the fabricated ones.


2021 ◽  
pp. 2100653
Author(s):  
Gyeong‐Su Park ◽  
Kyung Suk Min ◽  
Hyuksang Kwon ◽  
Sangwoon Yoon ◽  
Sangwon Park ◽  
...  

Plasmonics ◽  
2021 ◽  
Author(s):  
Mohammad Rakibul Islam ◽  
Fahim Yasir ◽  
Md. Rakib Hossain Antor ◽  
Mahmudul Hassan Turja ◽  
Ashikur Rahman ◽  
...  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kohei Shimanoe ◽  
Soshi Endo ◽  
Tetsuya Matsuyama ◽  
Kenji Wada ◽  
Koichi Okamoto

AbstractLocalized surface plasmon resonance (LSPR) was performed in the deep ultraviolet (UVC) region with Al nanohemisphere structures fabricated by means of a simple method using a combination of vapor deposition, sputtering, and thermal annealing without top-down nanofabrication technology such as electron beam lithography. The LSPR in the UV region was obtained and tuned by the initial metal film thickness, annealing temperature, and dielectric spacer layer thickness. Moreover, we achieved a flexible tuning of the LSPR in a much deeper UVC region below 200 nm using a nanohemisphere on a mirror (NHoM) structure. NHoM is a structure in which a metal nanohemisphere is formed on a metal substrate that is interposed with an Al2O3 thin film layer. In the experimental validation, Al and Ga were used for the metal hemispheres. The LSPR spectrum of the NHoM structures was split into two peaks, and the peak intensities were enhanced and sharpened. The shorter branch of the LSPR peak appeared in the UVC region below 200 nm. Both the peak intensities and linewidth were flexibly tuned by the spacer thickness. This structure can contribute to new developments in the field of deep UV plasmonics.


RSC Advances ◽  
2015 ◽  
Vol 5 (31) ◽  
pp. 23990-23998 ◽  
Author(s):  
Gaoling Liang ◽  
Zhongjun Zhao ◽  
Yin Wei ◽  
Kunping Liu ◽  
Wenqian Hou ◽  
...  

A simple, label-free and cost-effective localized surface plasmon resonance (LSPR) immunosensing method was developed for detection of alpha-fetoprotein (AFP).


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hyeong-Min Kim ◽  
Dae Hong Jeong ◽  
Ho-Young Lee ◽  
Jae-Hyoung Park ◽  
Seung-Ki Lee

AbstractA simple optical fiber sensor based on localized surface plasmon resonance was constructed for direct and rapid measurement of thyroglobulin (Tg). Specific tests for Tg in patients that have undergone thyroidectomy are limited because of insufficient sensitivity, complicated procedures, and in some cases, a long time to yield a result. A sensitive, fast, and simple method is necessary to relieve the psychological and physical burden of the patient. Various concentrations of Tg were measured in a microfluidic channel using an optical fiber sensor with gold nanoparticles. The sensor chip has a detection limit of 93.11 fg/mL with no specificity for other antigens. The potential applicability of the Tg sensing system was evaluated using arbitrary samples containing specific concentrations of Tg. Finally, the sensor can be employed to detect Tg in the patient’s serum, with a good correlation when compared with the commercial kit.


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