Plasmon electro-optic effect in a subwavelength metallic nanograting with a nematic liquid crystal

Nematic liquid crystal alignment on subwavelength metal gratings

“…Based on the FT spectrum of the TM mode, and taking into account the value of the ordinary refractive index known with a high accuracy ( n o = 1.527 at 546 nm [ 10 ]) together with its low spectral dispersion (d n o /dλ ≈0.0001 nm −1 ), an accurate value of the local LC layer thickness can be evaluated as d local = L TM /2 n o = 5.1 ± 0.05 μm. The inaccuracy is defined by spectral dispersion of the ordinary refractive index.…”

“…In our recent work, we showed that liquid crystals strongly affect both the plasmon resonance and light polarization properties of subwavelength metal gratings [ 9 ]. Meanwhile, these gratings can also be used as nanoelectrodes, which allow the LC to be driven by an electric field, enabling a very fast electro-optical effect due to the influence of the adjacent liquid crystal layer on the plasmonic resonance [ 10 ]. In all of these effects, the alignment of LC molecules on a metallic grating is of principal significance.…”

Liquid-Crystal Metasurfaces Self-Assembled on Focused Ion Beam Patterned Polymer Layers: Electro-Optical Control of Light Diffraction and Transmission

“…While the potential advantages of nonlinear and tunable optical metasurfaces are clear, the problem of altering the optical response of their submicrometer-scale solid-state constituents (based on noble metals, semiconductors, or dielectrics) remains challenging. The prospects of combining metamaterials and metasurfaces with liquid crystals (LCs), the most explored and exploited class of tunable optical media, have been early recognized. , Very different combinations of LCs with metallic − and dielectric − metasurfaces have been studied in the past decade.…”

Superperiodic Liquid-Crystal Metasurfaces for Electrically Controlled Anomalous Refraction

“…Prospects of combining solid-state nanostructures with soft-matter materials that are highly susceptible to various external factors were recognized more than a decade ago, as first tunable combinations of metamaterials and metasurfaces with liquid crystals (LCs) were proposed. , Since then, very different modifications of LC-metallic − and LC-dielectric − metasurface hybrids have demonstrated the feasibility of tuning by temperature, moderately powerful light, and voltage. From the practical point, compared to conventional LC-based devices, the performance of such hybrids is not always impressive: simple replacement of conventional polarizers and filters with sophisticated nanostructures drastically increases the complexity but does not automatically grant new performance features.…”

“…From the practical point, compared to conventional LC-based devices, the performance of such hybrids is not always impressive: simple replacement of conventional polarizers and filters with sophisticated nanostructures drastically increases the complexity but does not automatically grant new performance features. Qualitative improvements have been achieved by utilizing the LC environment for tuning the electromagnetic resonances hosted by metasurface elementsplasmon resonances of metallic structures , and Mie-type resonances of dielectric particles. , Being determined by reorientation of small adjacent LC volumes, such tuning can be much faster than the switching of LC bulk, allows reducing the LC-cell thickness and building micrometer-sized pixels. As a natural trade off, relying on resonances substantially reduces the operational bandwidths.…”