Engineering nanostructures with exceptionally high-Q resonances mediated by the Fano-type hybridization between discrete states associated periodicity of structure and broadband excited on constituent scatterers are emerging field in optics photonics. These collective lattice (CLRs) attracted a lot attention recent years due to number their exciting applications sensing, optical filtering, structural color printing, fluorescence enhancement, nanoscale lasing, nonlinear optics, which resulted...

Collective lattice resonances (CLRs) in finite-sized $ 2D $2D arrays of dielectric nanospheres have been studied via the coupled dipole approximation. We show that even for sufficiently large arrays, up to 100 \times $100×100 nanoparticles (NPs), electric or magnetic CLRs may differ significantly from ones calculated infinite with same NP sizes and interparticle distances. The discrepancy is explained by existence a strong cross-interaction between dipoles induced at NPs lattices, which...

Large scale simulations are performed by means of the transfer-matrix method to reveal optimal conditions for metal-dielectric core-shell particles induce largest fluorescence on their surfaces. With commonly used plasmonic cores (Au and Ag) dielectric shells (SiO2, Al2O3, ZnO), core shell radii determined reach maximum enhancement each wavelength within 550~850 nm core) 390~500 (Ag bands, in both air aqueous hosts. The peak value achievable factors nanoparticles, taken over entire interval,...

We present a computer code for calculating near- and far-field electromagnetic properties of multilayered spheres. STRATIFY is one-of-a-kind open-source package that allows efficient calculation near-field, energy density, total energy, radiative non-radiative decay rates dipole emitter located in any (non-absorbing) shell (including host medium), fundamental cross-sections sphere, all within single program. Because its speed broad applicability, our valuable tool analysis numerous light...

A thorough analysis of the emission via magnetic dipole (MD) transition, called light below, trivalent rare-earth ions in or near dielectric homogeneous spheres has been performed. In search for enhancement fluorescence from light, one faces difficult task identifying regions where combined due to multiple electric (ED) transitions becomes negligible compared MD transition. We have succeeded a number configurations with sphere parameters and radial position emitter wherein branching ratio...

Regular arrays of plasmonic nanoparticles have brought significant attention over the last decade due to their ability support localized surface plasmons (LSPs) and exhibit diffractive grating behavior simultaneously. For a specific set parameters (i.e., period, particle shape, size, material), it is possible generate super-narrow lattice resonances (SLRs) that are caused by interference LSP Rayleigh anomaly. In this letter, we propose structures based on regular 2D TiN nanodisks high-Q SLRs...

Collective lattice resonances in disordered 2D arrays of spherical Si nanoparticles (NPs) have been thoroughly studied within the framework coupled dipole approximation. Three types defects analyzed: positional disorder, size and quasi-random disorder. We show that disorder strongly suppresses either electric (ED) or magnetic (MD) coupling, depending on axis along which NPs are shifted. Contrarily, affects only MD response, while ED resonance can be almost intact, configuration. Finally,...

Metal halide perovskite materials have been extensively explored in modern photonic devices. Photonic crystals (PCs) are periodic structures with specific optical properties, such as stop bands and “slow photon” effects, which can tailor the propagation distribution of photons photoelectric PCs recent years widely to significantly improve performance luminescent and/or Therefore, a full understanding key role further learning correct use photonic/photoelectric devices essential for realizing...

We consider propagation of surface plasmon polaritons in linear chains equidistant metallic nanospheroids. show that, for suitably chosen parameters, the is free spatial decay spite full account absorptive losses metal.

Collective lattice resonances (CLRs) emerging under oblique incidence in 2D finite-size arrays of Si nanospheres have been studied with the coupled dipole model. We show that hybridization between Mie localized on a single nanoparticle and angle-dependent grating Wood–Rayleigh anomalies allows for efficient tuning CLRs across visible spectrum. Complex nature dielectric particles both electric (ED) magnetic (MD) paves way selective flexible either ED or MD CLR by an appropriate variation...

Mostly forsaken, but revived after the emergence of all-dielectric nanophotonics, Kerker effect can be observed in a variety nanostructures from high-index constituents with strong electric and magnetic Mie resonances. Necessary requirement for existence response limits use generally non-magnetic conventional plasmonic effect. In spite this, we demonstrate here first time lattice regular Al nanostructures. Collective oscillations emerging delicate interplay between Rayleigh anomalies...

We investigate numerically the propagation of steady-state monochromatic surface plasmon polaritons (SPPs) in curved chains metal nanoparticles various spheroidal shapes. discuss SPP (decay amplitude), polarization conversion due to coupling orthogonally polarized SPPs, and electromagnetic field localization near-field vicinity a chain.

The modified long-wavelength approximation (MLWA), a next order beyond the Rayleigh limit, has been applied usually only to dipole $\ell=1$ contribution and for range of size parameters $x$ not exceeding $x\lesssim 1$ estimate far- near-field electromagnetic properties plasmonic nanoparticles. Provided that MLWA functional form $T$-matrix in given channel $\ell$ is limited ratio $T\sim iR/(F+D-iR)$, where $F$ familiar size-independent Fr\"ohlich term $R\sim {\cal O}(x^{2\ell+1})$ radiative...

We show that in metal-dielectric core–shell nanoparticles, unusually thick dielectric coatings can produce extreme fluorescence enhancement with an factor F̅ ≳ 3000 for emitters located on the surface or interior of shell Au@dielectric spherical particles under realistic conditions, even 100% intrinsic quantum yield. Thick facilitate high-quality transverse electric (TE) multipole (l = 7) resonances which are shown as major cause reported extraordinary values F̅.

The interaction of non-monochromatic radiation with two types arrays comprising both plasmonic and dielectric nanoparticles has been studied in detail. We have shown that nanoparticle provide a complete selective reflection an incident plane wave within narrow spectral line collective lattice resonance Q-factor $10^3$ or larger, whereas refractory TiN chemically stable Au demonstrated high-Q resonances moderate reflectivity. position these lines is determined by the period, as well size,...

An experimental demonstration of directivities exceeding the fundamental Kildal limit, a phenomenon called superdirectivity, is provided for spherical high-index dielectric antennas with an electric dipole excitation. A directivity factor about 10 total efficiency more than 80% antenna having size third wavelength was measured. High are shown to be associated constructive interference particular and magnetic modes open resonator. Both analytic solutions point full-wave rigorous simulation...

We obtain exact analytic expressions for (i) the electromagnetic energy radial density within and outside a multilayered sphere (ii) total stored its core each of shells. Explicit special cases lossless shell are also provided. The general solution is based on compact recursive transfer-matrix method validity includes magnetic media. theory illustrated examples electric field enhancement various metallo-dielectric silica-gold spheres. User-friendly MATLAB code which theoretical treatment,...

Using the extended discrete interaction model and Mie theory, we investigate tunability of optical polarizability small metallic nano-shells. We show that spectral positions symmetric antisymmetric dipolar plasmon resonances vary with ratio particle radius to hole in a manner similar one predicted for uniform nano-shells using semiclassical approach two coupled harmonic oscillators. that, according model, are also present 2-13 nm size region same functional dependence seen larger previously...

Understanding the infrared (IR) spectral response of materials as a function their morphology is not only fundamental importance but also contemporary practical need in analysis biological and synthetic materials. While significant work has recently been reported understanding spectra particles with well-defined geometries, we report here on samples that consist collections particles. First, theoretically model multiple scattering effects computationally predict impact local particles'...

We have studied light induced processes in nanocolloids and composite materials containing ordered disordered aggregates of plasmonic nanoparticles accompanied by their strong heating. A universal comprehensive physical model that combines mechanical, electrodynamical, thermal interactions at nanoscale has been developed as a tool for investigations. This was used to gain deep insight on phenomena take place nanoparticle under high-intensity pulsed laser radiation resulting the suppression...

Photon upconversion (UC) is the sequential absorption of two or more low frequency photons and subsequent emission light at a higher frequency. Because large number potential applications this anti-Stokes process, extensive studies UC have taken place in last decades. The most crucial challenge field development an efficient strategy to enhance inherently efficacy process. Among various intensively developed approaches, local tailoring electromagnetic with metal nanoparticles (MNPs) position...