An ultra-broadband wavelength-selective anisotropic plasmonic metasurface

Laser Physics Letters. 2020. Vol. 17. No. 10. P. 105901.

Y G Vainer, Калмыков А. С., Melentiev P. N., Balykin V. I., Kirtaev R. V., Negrov D. V.

We offer and demonstrate a new type of plasmonic metasurface for sensorics and
surface-enhanced Raman spectroscopy (SERS) spectroscopy, characterized by a wide spectral
range of sensitivity from 450 nm to 850 nm. The metasurface is formed by Ag nanoparticles of
different sizes. The metasurface has clear anisotropy formed by the Ag nanoparticles’
size-dependent plasmonic resonances. The resonant wavelength of the metasurface is linearly
changed in one direction on a metasurface realizing a wavelength to space conversion and
remains the same in the other direction. The metasurface has advantages for use in different
applications of optical microscopy and SERS diagnostics, since it simultaneously provides a
strong optical signal amplification of up to 4×107 as well as a wavelength to space conversion
with a 10 nm spectral resolution. We show the fabrication of the anisotropic plasmonic
metasurface by the use of a robust approach based on Ag nanoparticle self-assembly during a
molecular-beam-epitaxy growth process. We demonstrate an application of the metasurface for
the fluorescence detection of low concentrations of dye molecules (Cy-7.5) and the
surface-enhanced Raman spectroscopy of an organic molecular monolayer (Alq3)

Keywords: Raman spectroscopy, nanoparticles, наночастицы, surface-enhanced Raman spectroscopy, metasurfaces, метаповерхности, anisotropic plasmonic metasurface, field enhancement, cпектроскопия комбинационного рассеяния света, гигантское комбинационное рассеяние света, анизотропная плазмонная метаповерхность, возрастание напряженности поля