Final Report Summary - PLASMETA (Plasmonic Metamaterials)
This ERC project involved the design, fabrication, and application of plasmonic metamaterials, composed of nanoscale metal/dielectric architectures. It focused on the demonstration of:
1) Plasmonic metamaterials with unusual optical properties that do not occur in nature.
We have fabricated metal/dielectric multilayer geometries of which the effective optical properties are determined by the plasmonic coupling between the individual layers. We showed how the dielectric constant can be continuously tuned from negative to positive values in the UV-VIS-IR spectral range. By designing the layer geometry we fabricated materials with an isotropic effective refractive index n=-1. A flat lens operating in the UV was demonstrated using this material. A three-dimensional optical metamaterial composed of coaxial plasmonic cavities was made and showed a polarization-independent negative effective index.
2) Plasmonic and dielectric metasurface and metamaterial architectures for light trapping in ultra-thin solar cells.
We demonstrated that silver nanowire networks act as effective transparent electrical conductors. We have developed a large-area soft-imprint technique to replicate metal nanowire networks on silicon and polymer solar cells. In parallel, we have discovered a plasmo-electric effect, in which off-resonant optical excitation of arrays of nanoholes made in a Au film generates a photovoltage. We evaluated the use of dielectric metasurfaces composed of dielectric cylinders as light coupling and trapping geometries. We identified the role of electric and magnetic resonances in these cavities and experimentally measured their optical spectra and mode profiles using angle-resolved cathodoluminescence imaging spectroscopy.
3) Demonstration of coupling between light and mechanical motion in plasmonic optomechanical nanocavities.
We designed nanoscale plasmomechanical metal-insulator-metal Fabry-Perot cavities using gold-coated silicon-nitride membranes and detected from the scattering spectrum the thermally driven motion at room temperature at an amplitude as small as 10 picometer. We demonstrated parallel transduction of mechanical motion of an array of gold-coated silicon nitride nanomechanical beams enabling the readout of multiple mechanical resonators in a single measurement. A photothermally driven parametric amplification effect was observed indicating the possibility of plasmonic mechanical actuation. The smallest plasmomechanical cavity was composed of a single plasmonic dimer antenna placed on a single silicon-nitride nanomechanical oscillator.
1) Plasmonic metamaterials with unusual optical properties that do not occur in nature.
We have fabricated metal/dielectric multilayer geometries of which the effective optical properties are determined by the plasmonic coupling between the individual layers. We showed how the dielectric constant can be continuously tuned from negative to positive values in the UV-VIS-IR spectral range. By designing the layer geometry we fabricated materials with an isotropic effective refractive index n=-1. A flat lens operating in the UV was demonstrated using this material. A three-dimensional optical metamaterial composed of coaxial plasmonic cavities was made and showed a polarization-independent negative effective index.
2) Plasmonic and dielectric metasurface and metamaterial architectures for light trapping in ultra-thin solar cells.
We demonstrated that silver nanowire networks act as effective transparent electrical conductors. We have developed a large-area soft-imprint technique to replicate metal nanowire networks on silicon and polymer solar cells. In parallel, we have discovered a plasmo-electric effect, in which off-resonant optical excitation of arrays of nanoholes made in a Au film generates a photovoltage. We evaluated the use of dielectric metasurfaces composed of dielectric cylinders as light coupling and trapping geometries. We identified the role of electric and magnetic resonances in these cavities and experimentally measured their optical spectra and mode profiles using angle-resolved cathodoluminescence imaging spectroscopy.
3) Demonstration of coupling between light and mechanical motion in plasmonic optomechanical nanocavities.
We designed nanoscale plasmomechanical metal-insulator-metal Fabry-Perot cavities using gold-coated silicon-nitride membranes and detected from the scattering spectrum the thermally driven motion at room temperature at an amplitude as small as 10 picometer. We demonstrated parallel transduction of mechanical motion of an array of gold-coated silicon nitride nanomechanical beams enabling the readout of multiple mechanical resonators in a single measurement. A photothermally driven parametric amplification effect was observed indicating the possibility of plasmonic mechanical actuation. The smallest plasmomechanical cavity was composed of a single plasmonic dimer antenna placed on a single silicon-nitride nanomechanical oscillator.