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1

Diminutive left-handed plasmonic nanoantenna-lens system in optical realm: ultraviolet emission and flat lens application

Rajput Monika, Dabas Bhawana, Saini Than Singh, Mehta Neeru

Optica Applicata

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2019

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Vol. 49, nr 4

679--692

EN

In present paper, a tunable left-handed plasmonic nanoantenna is designed to attain ultraviolet emission through a second harmonic generation with a phase harmonic condition. For the devised structure, the dispersion properties and negative values of the magnetic permeability and the electric permittivity show that the designed structure is left-handed for the primary wave (red light) and right-handed for the second harmonic wave (ultraviolet light). The 3D finite-difference time-domain method is employed to reveal its nonpareil skills (i.e. immense left-handed transmission efficiency and far-field spectrum exhibiting directionality). Attained results by numerical calculation for the second harmonic generation are accomplished with finite-difference time-domain analysis. The impact of physical parameters on transmission and dispersion characteristics is also scrutinized. Furthermore, flat lens application for a red light region with a centered wavelength at λ = 650 nm from the guileless design of LHM with no aberration is triumphed. Ultimately, a multifunction left-handed material is designed revealing tremendous potential to amass and abridge future applications in one architecture.

2

Phase and group velocities of surface waves in left-handed material waveguide structures

Taya S. A., Elwasife K. Y., Qadoura I. M.

Optica Applicata

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2017

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Vol. 47, nr 2

307--318

EN

We assume a three-layer waveguide structure consisting of a dielectric core layer embedded between two left-handed material claddings. The phase and group velocities of surface waves supported by the waveguide structure are investigated. Many interesting features were observed such as normal dispersion behavior in which the effective index increases with the increase in the propagating wave frequency. The phase velocity shows a strong dependence on the wave frequency and decreases with increasing the frequency. It can be enhanced with the increase in the guiding layer thickness. The group velocity peaks at some value of the normalized frequency and then decays.

3

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

Taya S. A., El-Amassi D. M.

Opto-Electronics Review

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2015

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Vol. 23, No. 3

214-221

EN

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.

4

Transmission of polarized light in LHM and RHM materials with periodic refractive index

Garus S., Garus J., Nabiałek M., Błoch K., Szota M.

Journal of Achievements in Materials and Manufacturing Engineering

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2014

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Vol. 65, nr 2

79--85

EN

Purpose: The paper presents the implementation of the Transfer Matrix Method algorithm using Mathematica and the impact of the structure discretization steps number on the filters transmission. Tested materials were made with periodically varying refractive index. Design/methodology/approach: The properties of the filter transmission made of a materials having a periodically varying refractive index were analyzed. The study used a Transfer Matrix Method algorithm. The materials have a thickness of one micrometer. The refractive index of the analyzed material changed sinusoidally with a wavelength of 500nm. Sinusoid quantizing was performed each for 8, 16, 32, 50 and 60 layers. Findings: Maps show the nature of the transmission bands. Band structure of RHM materials (positive refractive index) is similar to the structure of the filter constructed of LHM material, characterized by a negative refractive index. Transmission band in a left-handed material has less width at half maximum. Thirty two layers discretization stabilizes the simulations of the tested materials filtration properties. Research limitations/implications: The paper had not been analyzed for materials with extinction coefficient different from zero. It would be worthwhile to conduct research for materials with variable refractive index of a different nature, for example a triangular or saw tooth shape. Practical implications: Analysis of the filter materials for a variety of photonic structures allows the prediction and design of materials with specified properties. These tests allow to design filters and mirrors for with very good applications parameters. Originality/value: The influence of the discretization level of continuous medium with periodically changing material properties on the transmission map stability was analyzed.

5

Lossy double negative guiding layer optical sensors

El-Khozondar H. J., Taya S. A., Shabat M. M., Mehjez E. M.

Opto-Electronics Review

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2011

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Vol. 19, No. 3

277-281

EN

We proposed a three-layer waveguide as an optical sensor for homogeneous sensing applications. A guiding layer of the proposed structure is considered as lossy left-handed material (LHM) with simultaneously the complex negative electric permittivity µ and the complex negative magnetic permeability µ. We also assume a cladding layer to have an intensity-dependent refractive index. Sensitivity of the proposed optical waveguide sensor is derived and its dependence on different parameters of a waveguide is studied.

6

Propagation of polarized light through optical nanosuperlattices

Tarnowski K., Salejda W., Tyc M.H.

Optica Applicata

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2007

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Vol. 37, nr 4

387-396

EN

We investigate numerically transmittance of polarized electromagnetic wave through periodic and aperiodic binary multilayered nanostructures made of left- and right-handed materials. The transmittance is calculated as a function of light wavelength and incidence angle as well as ordering, refractive indices and thicknesses of superlattice layers. Thanks to extension of the transfer matrix formalism over the case of complex refraction angles, such effects as tunnelling, absorption and strong dispersion in left-handed metamaterials are taken into account. We find that these effects cannot be neglected and cause new transmission bands to appear in the areas where total internal reflection in a single metamaterial layer occurs.

7

Identifying magnetic response of split-ring resonators at microwave frequencies

Aydin K., Ozbay E.

Opto-Electronics Review

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2006

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Vol. 14, No. 3

193-199

EN

In this study we provide experimental methods to identify the magnetic resonance of split ring resonators (SRR) at the microwave frequency regime. Transmission measurements were performed on both single SRR unit cell and periodic arrays of SRRs. The magnetic response of the SRR structure was demonstrated by comparing the transmission spectra of SRRs with closed ring resonators (CRR). Effects of the changes in the effective dielectric constant of the SRR medium on the band-gaps of SRR are investigated experimentally. SRRs not only exhibit a magnetic resonance band gap but also a band gap due to the electric resonance. Finally, we present the effect of electric coupling to the magnetic resonance of bianisotropic SRRs by utilizing SRRs with different orientations, and incident electromagnetic wave polarizations.