Ultraviolet surface-enhanced Raman scattering at the plasmonic band edge of a metallic grating

Abstract

Surface-enhanced Raman Scattering (SERS) is studied in sub-wavelength metallic gratings on a substrate using a rigorous electromagnetic approach. In the ultraviolet SERS is limited by the metallic dampening, yet enhancements as large as 10(5) are predicted. It is shown that these enhancements are directly linked to the spectral position of the plasmonic band edge of the metal/substrate surface plasmon. A simple methodology is presented for selecting the grating pitch to produce optimal enhancement for a given laser frequency.

Super Absorbing Ultraviolet Metasurface

“…This EF is already close to those values obtained by double-resonance substrates with mixed metallic dimers for near-infrared wavelengths [30] and periodic metallic nanowire arrays for visible wavelengths [31]. Therefore, the numerical modeling results demonstrate that our super absorbing metasurface is promising to achieve better enhancement than previously reported nanopatterned Al-based SERS substrates at UV wavelengths [32] due to the strongly enhanced localization effect. Moreover, our design has great tolerance to incident angles, polarization states, thus releasing the challenging requirements on illumination conditions.…”

Uniform distribution of Ag particles upon imprinted polymer grating for Raman signal enhancement

“…There are different approaches to generate the SERS enhancement, of which different plasmonic nanostructures, such as metallic gratings [8][9][10] and dielectric subwavelength structures [11,12] are the most common. These nanostructures, manufactured by nanofabrication techniques, provide enhancements with good repeatability but are rather expensive and time consuming to fabricate.…”

Size- and shape-dependent plasmonic properties of aluminum nanoparticles for nanosensing applications

“…Silver, for example, is very easily oxidized, which reduces the sensing response, while gold is lossy at lower wavelengths due to interband transitions. Aluminum is a promising material for plasmonic applications in the wavelength region below 500 nm, especially in the deep-UV region, due to its very high plasma frequency [12,13]. However, because aluminum is a reactive metal, its oxidation in atmospheres containing oxygen or aqueous solution, in contrast to silver, is self-limiting and stabilizes after the formation of a thin aluminum oxide layer.…”