Reflection through a parallel-plate waveguide formed by two graphene sheets

Reflection through a dielectric slab located between two graphene sheets is considered. The proposed parallel-plate waveguide is assumed to be symmetric with the substrate and cladding layers are air. The two graphene sheets are considered to be identical and having frequency-dependent surface conductivity σ(ω). The reflection through the proposed structure is investigated with the angle of incidence and the frequency of incident electromagnetic waves

Reflection and transmission from left-handed material structures using Lorentz and Drude medium models

The present article investigates theoretically the refection and transmission through a lossless dielectric slab embedded between two semi− infinite left− handed materials (LHMs) in which the electric permittivity and magnetic permeability are simultaneously negative. The LHM is assumed to be dispersive according to Lorentz as well as Drude medium model. The reflection and transmission coefficients are studied with the angle of incidence, frequency and slab thickness. The effect of the damping frequency is also investigated. It is found that the damping frequency has an insignificant effect on reflected, transmitted and loss powers. Band pass filter is one of the possible applications of the proposed structure

Reflected and transmitted powers of p-polarized electromagnetic waves through a dielectric slab surrounded by double negative materials

In this paper, reflected, transmitted, and loss powers of p-polarized electromagnetic waves through a lossless dielectric slab embedded between two double negative media are studied. Lorentz and Drude medium models are both considered for the dispersion of the double negative materials in the surroundings. The dependences of reflected, transmitted, and loss powers on the incidence angle, incident wave frequency, and dielectric slab thickness are investigated. The results reveal many interesting features. The damping frequency has a slight effect on reflected, transmitted, and loss powers in most waveguide configurations considered. Moreover, the loss power is small and can be significantly reduced by considering Drude dispersion model and careful choosing of the proposed structure parameters

Left-handed photonic crystal waveguide sensors

In this work, we examine analytically the propagation of TE polarized wave in a multilayer one dimensional photonic crystal consisting of alternate right-handed material and left-handed materials. The sensitivity of above-mentioned structure optical waveguide sensor is derived and investigated with various physical parameters of the structure

Design and analysis of multilayer waveguides containing nanoparticles for solar cells

A novel waveguide structure containing nanoparticles with various substrate media has been proposed to find out the transmission and reflections of the incident light on the proposed structure. The Transfer matrix method has been applied to study the transverse electric TE and the transverse magnetic TM waves at an Antireflection (AR) coating structure for silicon solar cells with a nanoparticles-dielectric layer. The transmission and reflection coefficients have been derived at different incident angles of light and for various substrate’s materials in wavelength region between 300 nm and 1200 nm. The numerical results, obtained by MAPLE software, highlight an enhancement of the transmission coefficient and reduction of the reflections for different substrate media

Design of novel graphene-waveguide sensor

The plasmon characteristics in multilayer grapheme film sandwiched by anisotropic dielectric and water cover have been investigated. The dispersion relation for the plasmon waves is obtained analytically and the behaviour of the guided modes are discussed under three distinct cases. It is found that the penetration depth of surface plasmons is highly dependent with the surrounding dielectrics and oriented optical axis. The sensitivity has also been obtained. The sensitivity is proven to be affected by different parameters including the graphene thickness, the operating frequency, and the oriented optical axis. Higher sensitivity have been obtained by tuning some physical parameters. The results may be helpful for the practical application of graphene-based optoelectronic sensors

Efficiency Enhancement of Solar Cell Using Metamaterials

In this work, Photovoltaic (PV) cell model with high absorption efficiency is introduced. The proposed four layer PV cell model consists of antireflection coating (ARC) layer on glass based and covered by metamaterial (MTM) bounded by air. The effect of the refractive index of MTM as well as the effect of the incident angle on the reflectance are considered. Results showed that the reflectance of the PV can be controlled by changing the reflectance index of MTM as well changing the incident angle

Extension of energy band gap in ternary photonic crystal using left-handed materials

We investigate the extension of energy band gap in one-dimensional ternary photonic crystal. We assume one of the layers constituting the ternary photonic crystal to be left-handed material (LHM) of simultaneously negative electric permittivity and magnetic permeability. The photonic crystal has the structure dielectric/LHM/dielectric. We show in this work, the energy band gap in one-dimensional ternary photonic crystal can be dramatically enlarged with the increase of the LHM layer thickness. Moreover, it can also be enlarged with the decrease of both the negative permittivity and permeability of the LHM layer. The effects of the angle of incidence and the number of layers are also investigated