Parisa Khajegi, Majid Rashidi-Huyeh,
Volume 15, Issue 1 (1-2021)
Abstract
Nobel metal nanoparticles (NPs) are widely used in various applications including optical and biological sensors, biomedicine, photocatalysts, electronics, and photovoltaic cells. The optical properties of gold NPs are surveyed in this paper under the Localized Surface Plasmon Resonance (LSPR) effect, which increases the light absorption and scattering at the LSPR wavelength. This LSPR frequency depends on various factors, including the shape and size of the particles as well as incident electromagnetic polarization. Here, the optical response of gold NPs with different shapes and sizes are investigated using the finite element method (FEM). The results show that the bandwidth, amplitude, and LSPR wavelength depend on the shape and dimensions of the NPs as well as the polarization of the incident light. The LSPR wavelength changes from 500 to 650 nm for different shapes of the gold NPs including sphere, octahedral, cube, ellipsoid, triangle, and with identical volume. To study the NP size effect on the optical properties, the absorption and scattering cross-sections (CSs) are also investigated for different sizes of NPs. The results show a redshift in the LSPR wavelength by increasing the NP size.
Neda Roostaei, Seyedeh Mehri Hamidi,
Volume 17, Issue 2 (6-2023)
Abstract
Color vision deficiency (CVD), or color blindness, is a prevalent ocular disorder that hinders the recognition of different colors, affecting many people worldwide (8−10% of males and 0.4−0.5% of females). Recently, there has been a significant focus on plasmonic nanostructures as an alternative to chemical dyes for managing color blindness due to their remarkable characteristics and the tunability of plasmonic resonances. In this work, the plasmonic glasses based on silver nanoparticles with a TiO2 thin layer coating were fabricated using the sputtering technique and proposed for blue-yellow (tritanopia) CVD management. The proposed plasmonic glasses based on silver nanoparticles are more selective than commercial Enchroma glasses because of the tunability of plasmonic properties of silver nanoparticles by controlling their morphology, which provides insights for applications of color vision deficiency improvement. Also, the antibacterial activity of the proposed plasmonic glasses based on silver nanoparticles was investigated against E. coli and S. aureus bacteria, which have exhibited effective antibacterial properties. The results indicate that the silver nanoparticle-based glasses not only aid in tritanopia management but also offer potential for antibacterial applications such as implant coatings.
