Plasmonic nanospherical dimers for color pixels

Abstract

Display technologies are evolving more toward higher resolution and miniaturization. Plasmonic color pixels can offer solutions to realize such technologies due to their sharp resonances and selective scattering and absorption at particular wavelengths. Metal nanosphere dimers are capable of supporting plasmon resonances that can be tuned to span the entire visible spectrum. In this article, we demonstrate numerically bright color pixels that are highly polarized and broadly tuned using periodic arrays of metal nanosphere dimers on a glass substrate. We show that it is possible to obtain RGB pixels in the reflection mode. The longitudinal plasmon resonance of nanosphere dimers along the axis of the dimer is the main contributor to the color of the pixel, while far-field diffractive coupling further enhances and tunes the plasmon resonance. The computational method used is the finite-difference time-domain method. The advantages of this approach include simplicity of the design, bright coloration, and highly polarized function. In addition, we show that it is possible to obtain different colors by varying the angle of incidence, the periodicity, the size of the dimer, the gap, and the substrate thickness.

Plasmonic Heating of Nanostructures

“…Even in the colder Nordic countries, solar energy can be harvested by using plasmonic nanoparticles in photovoltaic thermal (PVT) collectors. 262 The phenomenon of light scattering from plasmonic nanoparticles also has exciting applications; for instance, plasmonic nanoparticles can be used as nanoscopic color pixels in technologies requiring high resolution or miniaturization 263 or as optically trapped scatterers in 3D floating displays. 264 Also, thermoplasmonic effects have been exploited for photothermal imaging yielding supreme label-free tracking of nanometer-sized AuNPs 265 and for tracking carbon nanotubes within cells.…”

Symmetry Breaking in Oligomer Surface Plasmon Lattice Resonances

“…However, the far-field scattering can be positively influenced also by the presence in the unit cell of multiple close-gap nanodisks, giving rise to localized electromagnetic field hot spots within the gaps. 30,43,44 This combined effect leads to the narrow and well-defined transmission peak in the visible, present in experimental spectra, and even more apparent in numerical simulations (Figure 2b and in Supporting Information, Figure S6), where fabrication defects and tolerances are not taken into account.…”

“…The proposed multidisk structure can be particularly advantageous for color generation with respect to other efficient diffractively coupled plasmonic filters, such as recently reported nanopatches, nanodisks, and nanocrosses. , In fact, the far-field spectrum of the array takes advantage of the diffractive coupling, which can lead to large quality factor values. However, the far-field scattering can be positively influenced also by the presence in the unit cell of multiple close-gap nanodisks, giving rise to localized electromagnetic field hot spots within the gaps. ,, This combined effect leads to the narrow and well-defined transmission peak in the visible, present in experimental spectra, and even more apparent in numerical simulations (Figure b and in Supporting Information, Figure S6), where fabrication defects and tolerances are not taken into account.…”

Evaluation of fiber-optic phase-gradient meta-tips for sensing applications

“…After the groundbreaking proposal by Yu et al, 22 where generalized Snell’s laws were formulated and implemented via MSs based on V-shaped plasmonic nanoantennas, the field of MSs has rapidly developed and currently represents one of the most active and fast-pacing research areas (see, e.g. previous studies 23 –35 for a sparse sampling of key contributions and recent reviews).…”