RESUMO
The efficient electric field enhancement due to coating a dielectric wedge by plasmon-carrying nanowires has been demonstrated numerically within the framework of the finite-difference frequency-domain method. The numerical simulations show increasing of electric field intensity in the near-field region of the dielectric wedge coated by silver nanowires in the regime of local plasmon excitation up to 100 times versus the uncoated case.
Assuntos
Eletricidade , Terapia a Laser/métodos , Fenômenos ÓpticosRESUMO
A new approach to the formation of a 1D planar periodicity on the front of a plasmonic photodetector based on Schottky barrier is proposed. It allows forming a 1D planar periodicity with corrugation at the "metal/environment" interface by laser interference lithography using embedded chalcogenide wires, whereas the "metal/semiconductor" interface is flat that leads to reducing of surface recombination losses at Shottky barrier in contrary to the conventional technology for forming corrugated metal films on the semiconductor surface requiring chemical etching of the semiconductor substrate. In this case, the metal film interfaces are quasi-anticorrelated as opposed to correlated ones in the conventional technology. It has been theoretically predicted that the polarization sensitivity (T p /T s ) strongly depends on the cross-sectional shape of chalcogenide wires and reaches a value of 8. Furthermore, it was theoretically found that the maximum sensitivity of the signal intensity on the environment refractive index is three times larger than for an equivalent structure obtained by conventional technology. Comparison of experimental data for the photocurrent in the case of two types of correlation between metal film interfaces demonstrates good agreement with numerical simulations.
RESUMO
The hybridization of the plasmonic and guided modes in the case of one-dimension photonic crystal based on Bragg mirror terminated by a corrugated metal film has been demonstrated theoretically. The simulations have showed that the hybrid plasmonic-photonic mode is characterized by low broadening due to redistribution of the electric field intensity between photonic mode and surface plasmon polariton. It was found that the Q-factor and the polarisation sensitivity of these modes are about 144 and 25, respectively, that is 3 times greater than for surface plasmon polariton exciting in similar structure without Bragg mirror.
RESUMO
We review the recently emerged class of hybrid metal-dielectric colloidal photonic crystals. The hybrid approach is understood as the combination of a dielectric photonic crystal with a continuous metal film. It allows to achieve a strong modification of the optical properties of photonic crystals by involving the light scattering at electronic excitations in the metal component into moulding of the light flow in series to the diffraction resonances occurring in the body of the photonic crystal. We consider different realizations of hybrid plasmonic-photonic crystals based on two- and three-dimensional colloidal photonic crystals in association with flat and corrugated metal films. In agreement with model calculations, different resonance phenomena determine the optical response of hybrid crystals leading to a broadly tuneable functionality of these crystals.
Assuntos
Coloides/química , Óptica e Fotônica , Cristalização , Metais/química , Modelos Moleculares , Ressonância de Plasmônio de SuperfícieRESUMO
An improved method for the calculation of light-matter interaction that appears with the light propagation through multilayer periodically corrugated structures consisting of any dielectric or absorptive media is reported. The method is based on the differential formalism for a system of Maxwell's equations when the boundary conditions are simplified by the introduction of a curvilinear nonorthogonal coordinate system. The solution for electromagnetic fields was written in the form of the superposition of partial plane waves. The obtained method essentially reduces computation time and increases accuracy compared with the Chandezon method. For a numerical demonstration of the proposed method, calculation of long-range surface plasmon polaritons was performed. The presented method can be enhanced for calculations of light propagation through thin absorptive films with various periodic profiles at both film interfaces.
RESUMO
The enhancement of light transmittance through periodically relief thin absorptive film at surface plasmon polariton excitation conditions, as a function of relief interrelation, was considered theoretically. Our calculation of transmittance-reflectance through periodically relief thin absorptive film was performed in the framework of differential formalism. There are two basic relief interrelation forms, namely, correlated and anticorrelated ones. The obtained spectral and angular dependencies demonstrate an essential increase of surface plasmon polariton peaks in the case of anticorrelated corrugation of film in comparison with the correlated ones.