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The scattering of a linearly polarized electromagnetic plane-wave from a sphere composed of an orthorhombic dielectric–magnetic medium having concentric layer of the chiral material is considered. ...

A dual-core coupled silicon-rich nitride waveguide pumped at telecom wavelength, allowing more power-efficient conversion and dispersive wave engineering in the mid-infrared region up to 7μm wavelength by simulations is demonstrated.

In this paper, we investigated the surface plasmon resonance of metallo-dielectric core-shell nanoparticle in the near-infrared (NIR) regime of the light. The wavelength-dependent permittiv...

Using positive and/or negative phase velocity conditions, characteristics of a planar non-integer dimensional (NID) chiral interface are explored for specific values of NID parameter. For this purpose, discussion is divided into four cases. It is noted how characteristics of the interface changes when the situation is changed from one case to another. Impact of variation of NID parameter on the reflected power is also noted for each case.

The T matrix method can be formulated to study Beltrami planewave scattering by a sphere composed of an orthorhombic dielectric magnetic material immersed in a chiral medium. Whereas an ort...

Reflection and transmission characteristics of a planar interface of two non-integer dimensional (NID) chiral mediums have been explored in this paper. It is assumed that both constitutive and NID parameters, for mediums on two sides of the interface, have different values. Assuming a circularly polarized plane wave as incident wave, reflected powers are determined and their behaviors are discussed with respect to the NID parameters. Effects of NID parameters on the tunneling and rejection of powers have also been noted. It is noticed that NID parameters have strong effects on behavior of the reflected powers.

Purpose of the paper is to determine the Goos-Hanchen (GH) shift for fractional dual fields related to a planar interface. The fractional dual fields are considered as intermediate step between the two given fields; which are connected through the curl operator. In our discussion, TE and TM fields are the two given fields. By fractionalizing the curl operator, one can get the fractional dual fields. It is investigated how variation of order of the curl operator varies amplitude, phase and GH-shift for the fractional dual fields.

Radiation due to an electric line source placed under a planar dielectric slab of non-integer dimensional space is determined. It has been assumed that the non-integer dimensional dielectric slab is sandwiched between two integer dimensional dielectric mediums. Radiated fields are written in terms of unknown spectrums of propagating waves. The unknown spectrum functions are determined using the boundary conditions. Special cases have also been discussed to verify the derived results. Radiation pattern is given for different parameters related to the geometry.

Impact of non-integer dimensional (NID) dielectric–magnetic medium on the behavior of power transmitted and reflected from a planar NID Lorentz–Drude slab is analyzed for uniform electromagnetic plane wave excitation. The dispersive slab is terminated by NID dielectric–magnetic medium and dispersion in the slab has been indulge through the Lorentz–Drude model. It is assumed that medium inside the Lorentz–Drude slab and medium backing the slab are NID in direction perpendicular to surface of the slab but their dimensions are described by different NID parameters. According to the characteristics of the model, while the operating frequency increases the NID Lorentz–Drude slab operates as epsilon negative (ENG), double negative (DNG), mu negative (MNG), double positive (DPS) metamaterial respectively. Effect of NID parameter of the terminating medium, dielectric magnetic properties of the terminating medium and impact of their combination on the powers is noted one by one. It is noticed that parameters describing the NID dielectric–magnetic medium significantly change the behavior of powers. These parameters can be effectively used to control the power according to the requirements.

Solution for electromagnetic scattering from a perfect electric conducting strip buried in a planar grounded dielectric slab is determined by using the Kobayashi Potential Method. It is assumed that the dimension of mediums, above and within the slab, is non-integer in the direction normal to interface of the slab. The scattering problem is divided into two parts. In the first part, fields in the absence of strip are determined for plane wave excitation. In the second part, presence of the strip is taken into account. It has been assumed that spacings between the strip and interfaces of the slab are comparatively very larger than the wavelength of monochromatic operating frequency. Due to this assumption, scattered field after reflection from the interfaces has no interaction with the strip. In order to gains more insight, several special cases of the geometry are treated. Using saddle point method, far-zone scattered field for region above the grounded slab is also determined.

Theoretical study of the Goos-Hanchen (GH) shift for a planar interface of ordinary dielectric and non-integer dimensional (NID) dielectric media is presented. It is assumed that medium is NID in direction normal to the interface. Effects of the NID parameter on absolute value of the reflection coefficient, its phase, and lateral displacement along the interface is noted. Both parallel and perpendicular polarized incidence are considered in this regard.

Reflection and transmission characteristics of a planar interface, of non-integer dimensional (NID) dielectric-chiral mediums, are studied for oblique incident electromagnetic linearly polarized plane wave. For this purpose, reflected power for parallel and perpendicularly polarized incident wave is determined and analysed. NID dielectric-chiral nihility interface is also considered as a special case. It is noted that NID parameter and its variation has significant impact on electromagnetic characteristics of the interface under investigation. It can effect the existence and location of the Brewster angle. For a particular range of incident angle and specific value of the NID parameter, the interface may be used as reflection free interface. NID parameter may also be used to convert a reflection free interface into a reflecting interface.

Purpose of the present study is to investigate the reflection and transmission characteristics of a non-integer dimensional (NID) planar interface located in an unbounded homogeneous chiral medium. The medium is NID in direction normal to the interface and a parameter, called NID parameter, is used to model the NID characteristics of the medium. Interface exists due to unequal value of the NID parameters characterizing mediums lying on two sides of the interface. It is observed co and cross-components of reflected field have very significant effect of NID parameters. Special cases in which one and neither of the NID parameter is integer order have also been discussed.

Kobayashi potential method is applied to get the scattering behavior by a perfect electromagnetic conducting strip deeply buried underneath a flat dielectric slab. Using the two-dimensional solution of homogeneous Helmholtz’s equation, Fourier transformed representation of scattered field is written in terms of the unknown characteristic functions. Application of the boundary conditions on tangential components of electromagnetic fields gives dual integral equations (DIEs) which through Weber–Schafheitlin’s discontinuous integrals and Jacobi polynomials are used to satisfy the edge condition. The resulting DIEs are written in matrix equations, and those that involve infinite integrals are computed numerically. The saddle point method of integration is used to obtain an expression for the far-zone scattered field. To validate the results, obtained results are firstly compared with corresponding obtained through the physical optics method. The width of the strip, the thickness of the slab, and the angle of incidence of plane wave are taken as parameters to study their influence on the scattered field.

Interaction of light and matter can be controlled and manipulated by exploiting the properties of the isofrequency contours (IFCs) of a material. IFC in metamaterial/artificial anisotropic materials can be open and/or closed. The class of metamaterials with open IFC are known as hyperbolic metamaterials (HMMs)/indefinite media. HMMs support large wavevectors, which can lead to some important consequences, such as energy transfer (long range), metacavity lasers (subwavelength scale), sensors (high sensitivity), and hyperlenses (surpassing diffraction limit). Therefore, in this paper wavevector planes for media with open and closed IFCs are investigated with an aim to further differentiate them into regions supporting distinct electromagnetic modes, orientation of power, wavevector, and positive-negative phase velocities.

This paper deals with a theoretical study of chiral and dielectric media. Numerical results for polarizabilities have been investigated for chiral-chiral, chiral-dielectric, dielectric-chiral and dielectric-dielectric configuration. We have also discussed the effect of permittivity change on electric polarizaibility, magnetic polarizability and cross polarizabilities. Our aim is to give a comprehensive analysis of shielding effectiveness for different configurations of layered bi-isotropic spheres. Our findings include the diamagnetic character of chiral sphere. We present shielding effects as a function of material parameters: permittivity, permeability, and chirality. Results illustrate these effective parameters influence polarizabilities and on shielding effectiveness.

The investigation of core-shell nanoparticles has been greatly exciting in biomedical applications, as this remains of prime importance in targeted drug delivery, sensing, etc. In the present work, the polarizability and scattering features of nanoparticles comprised of nano-sized dielectric/metallic core-shell structures were investigated in the fractional dimensional (FD) space, which essentially relates to the confinement of charged particles. For this purpose, three different kinds of metals&mdash, namely aluminum, gold and silver&mdash, were considered to form the shell, having a common silicon dioxide (SiO2) nanoparticle as the core. It is noteworthy that the use of noble metal-SiO2 mediums interface remains ideal to realize surface plasmon resonance. The core-shell nanoparticles were considered to have dimensions smaller than the operating wavelength. Under such conditions, the analyses of polarizability and the scattering and absorption cross-sections, and also, the extinction coefficients were taken up under Rayleigh scattering mechanism, emphasizing the effects of a varying FD parameter. Apart from these, the tuning of resonance peaks and the magnitude of surface plasmons due to FD space parameter were also analyzed. It was found that the increase of FD space parameter generally results in blue-shifts in the resonance peaks. Apart from this, the usage of gold and silver shells brings in fairly large shifts in the peak positions of wavelengths, which allows them to be more suitable for a biosensing purpose.

Behavior of normalized polarizability of a multilayer sphere of non-integer dimensional dielectric materials placed in free space is presented. Normalized polarizability is calculated with respect to number of layers and value of non-integer dimensional parameter. Special case by taking value of non-integer dimensional parameter equal to three is obtained to validate present work by comparing it with already published work.

Behavior of transmitted and reflected power from a planar non-integer dimensional lossless dispersive slab, placed in free space, is explored for uniform electromagnetic plane wave excitation. Dispersion has been incorporated through the Lorentz-Drude model. As the frequency of excitation increases, the dispersive slab respectively behaves as epsilon positive, double negative, mu negative, double positive meta-material. Effects of variation of angle of incidence, width of the slab and frequency of excitation on behavior of the powers have been noted taking different values of the parameter modeling non-integer dimensional space.

The behavior of surface plasmon polaritons (SPPs) at a planar non-integer dimensional dielectric-metal interface has been studied for the first time. The dimension of the interface is shown to have a strong effect on the behavior of SPPs. Dimensions of both the half spaces are different from each other which can be used to distinguish between them besides their different wavenumbers. Lossless dielectric medium has non-integer dimensions while metal has integer dimension. Surface plasmon polaritons (SPPs) only exist for p-polarization and no surface modes exist for s-polarization because the partnering non-integer dimensional dielectric material is homogeneous (Polo and Lakhtakia, 2011). Two methods are used in order to verify the proposed idea. First method is named as so-called indirect method, by using this method, it has been observed that SPP waves are excited only at one incident angle [θi=54.87°] for p-polarized incidence. It has been investigated that the behavior of SPPs changes with change in order of non-integer dimension. The absorption of SPPs increases by decreasing dimensionality for p-polarization at the excitation angle. Second method is named as so-called direct method, according to this method, by solving the presented idea directly using SPP waves fields expressions in NID space, it is conceived that SPPs with same polarization state, but with different phase speeds, attenuation rates, along with propagation lengths can be directed by such interface which incorporates metal and a non-integer dimensional dielectric medium. The results achieved by both methods (so-called indirect and direct methods) complement each other tremendously, validating the efficiency of our proposed concept regarding propagation of SPP waves at a planar non-integer dimensional dielectric-metal interface. Furthermore, the effect of relative permittivity of non-integer dimensional dielectric medium on SPPs is also discussed. The conventional results for integer dimensional space can be recovered as a special case. Keywords: Surface plasmon-polariton waves, Non-integer dimensional dielectric medium, Metal, P-polarization, Non-integer dimensional (NID) space

The principal goal of this paper is to investigate the intermediate zones in electromagnetics when a radiation/scattering problem is modeled through Dirichlet Green's function. Field/potential quantities over two parallel observation flat planes are related by an integral transform with K as its kernel. The kernel of the integral transform may be divided into two parts: one is Km yielding contribution due to actual source and the other is Kn yielding image contribution. The fractional kernel Kν with fractional parameter ν can provide a unique way of interpreting the field in the intermediate zone. Moreover, use of this fractional kernel to study the Fresnel and Fraunhofer diffraction zones is also described. Result for corresponding static problem is obtained by applying the limit on this kernel.

The propagation of time harmonic linearly polarized wave in unbounded lossy/lossless noninteger dimensional space (NID) dielectric medium is investigated. It has been shown how the NID parameter changes the behavior of the propagating wave in the presence of losses. Then, it has been used as a source of excitation for an interface. A planar NID interface located in lossy dielectric medium is treated and its comparison has been made when the host medium is lossless or free-space. Furthermore, NID dielectric interface due to two lossy NID dielectric media is also investigated in this regard. The impact of different parameters, incident angle, real/imaginary part of the permittivity on reflection and transmission characteristics of a planar NID-interface/NID-dielectric interface is noted. Differences between the two cases are highlighted.

This manuscript studies the impact of non-integer dimensional (NID) space on cloaking and magnification introduced through polarly radially anisotropic (PRA) cylindrical shell/spherically radially anisotropic (SRA) spherical shell. By selecting appropriate value of ratio, between components of tensor permittivity, these structures in ordinary space ( α = 3 ) can yield cloaking and magnification under the quasi-static limit. In case of NID space ( α ≠ 3 ), PRA cylindrical shell can only yield cloaking. It has been shown that bound on anisotropy ratio get effected by the NID parameter in case of PRA shell. It has also been noted that magnification cannot be achieved using PRA shell in NID space. Further, cloaking and magnification of SRA shell remains independent of parameter describing NID space.

Quasi-static analysis of electromagnetic scattering from a radially uniaxial (RU) sphere is presented in this paper. RU dielectric sphere is placed in an unbounded fractional dimensional space. We investigate effects of fractional dimensional space on behavior of potential distribution due to the RU sphere. For this purpose, numerical results of electric potential for different dimensions of the fractional space have been presented and discussed.

In the present paper, the scattering characteristics of a magnetized plasma-coated topological insulator cylinder are formulated and analysed graphically. Field equations at each interface are expanded in terms of cylindrical wave vector functions by imposing extended classical wave-scattering theory. By applying the boundary conditions, scattering matrices are obtained in terms of scattered and transmitted coefficients. The obtained results are also compared with published results to display the accuracy of the present formulation under some special conditions. Changes in the bistatic echo widths of the topological insulator cylinder are also recorded by varying the anisotropic plasma parameters (i.e., the applied magnetic field, plasma density and effective collisional frequency).

A Goos–Hänchen shift (GHS) due to an orthorhombic biaxial slab with/without topological conducting states placed in isotropic media was investigated. The effect of varying host media, changing topological conducting states, and left/right asymmetries on the co/cross-polarized reflection coefficients and the corresponding GHS was investigated. Numerical calculations revealed that large negative/positive GHS occurs near the reflectance dips (local reflectance minimum) due to sudden changes in the amplitude of the reflection coefficient. Position and amplitude of the GHS near these reflectance dips are affected by anisotropy and surface admittance. Furthermore, numerical calculations also revealed that the GHS is left/right symmetric for an orthorhombic biaxial slab with/without topological conducting states. However, if the optic axes of a slab with/without a topological conducting state are rotated along any direction, the resulting GHS becomes left/right asymmetric.

In this article, analysis of the Goos Hanchen (GH) effect for an epsilon-near-zero (ENZ) slab, sandwiched between two different non-integer dimensional (NID) media, considering a plane wave as the source of excitation is presented. Both transverse electric and transverse magnetic polarizations are taken into account in this regard. The influence of variation of NID parameters on the reflection/ transmission coefficient and GH shift is examined. For value of the NID parameter equal to two, results already published in scientific literature are recovered.

Mathematical formulation for the far-zone field scattered by a cylindrical obstacle deeply buried beneath a planar dielectric slab has been presented. Method known as Kobayashi potential method has been employed for this purpose and transverse electric uniform plane wave has been used as a source of excitation. It has been assumed that dimension of space within slab is non-integer in the direction normal to planar interfaces of the slab. Moreover, it has also been assumed that distance of each interface of the slab from obstacle is very large as compared to size of the obstacle. Due to this assumption scattered field after reflection from the slab has no interaction with the obstacle and the situation has been called deeply buried. Field pattern has also been obtained and compared with the published work.

The gain properties of an axially slotted cylindrical antenna coated with eccentric layer of inhomogeneous material placed in different metamaterials have been investigated. The slot is assumed to be infinitesimally thin such that it can excite TE mode only. The radiated fields in region filled by inhomogeneous material are written in terms of modified Bessel and Hankel functions of non-integer order and the eccentricity is mathematically incorporated by employing Graf’s addition theorem. Numerical results to describe the radiation characteristics of antenna are presented and discussed while taking different profiles for the inhomogeneity, values of the eccentricity parameter, operating frequency, and type of host medium. It is observed that the radiation pattern can be controlled, from isotropic (omnidirectional) to directive one, by selecting suitable choice of the inhomogeneity profile and value of the eccentricity parameter. Another interesting feature of the antenna is found when it is embedded in zero index medium, in that case the exponent of the profile function ψ ( κ ρ ) has direct relationship with the number of main lobes in the radiation pattern.

The purpose of this paper is to examine the Goos–Hanchen-effect (GH-effect) for near-zero-index metamaterials taking fractional dual fields as the source of excitation. Fractional dual fields are intermediate states between the s -polarized and p -polarized fields. The behavior of reflection coefficient, corresponding phase, and GH-effect, for epsilon-near-zero (ENZ)/mu-near-zero (MNZ) metamaterial is analyzed. Both lossless and lossy ENZ/MNZ metamaterial are treated in this regard. Impact of variation of fractional parameter on the behavior of reported quantities is noted in detail.

Using Yasumoto and Oishi's energy flux method, Imbert-Fedorov shift for a planar interface of ordinary dielectric/non-integer dimensional-dielectric/chiral chiral/non-integer dimensional chiral media is theoretically investigated. In the case of non-integer dimensional-chiral chiral interface, the behavior of Imbert-Fedorov shift is noted for both co and cross components of the reflected field. It is noted that variation of chirality parameter impacts the Imbert-Fedorov shift; both positive and negative shifts can be obtained. Furthermore, varying the value of the non-integer dimensional parameter and the value of permittivity also affects the shift.

This paper investigates the electromagnetic cloaking features of a spherical dielectric nanoparticle enclosed by a uniform shell of the inhomogeneous chiral medium. The cloaking characteristics were analyzed in terms of the effective permittivity of the nanoparticle. In this regard, effective permittivity was analyzed as a function of the chirality parameter, radial permittivity, and inhomogeneity parameter of the medium filling the shell. The results show the unit effective permittivity of the proposed core–shell nanoparticle attribute to the cloaking property.

In present discussion, the idea of non-integer dimensional (NID) optoelectronics has been investigated. For this purpose, a nano-size sphere of any material (plasmonic or non-plasmonic) placed in NID space has been excited by an optical signal. Fields in the presence of sphere have been used to derive impedances. Reactance for the region inside the sphere is independent of NID parameter. Whereas, the capacitive and inductive behavior of impedance for the region outside the sphere can be controlled through material properties and NID parameter. This gives the existence of fringing capacitance and inductance.

Using Kobayashi potential method, mathematical formulation and solution have been provided for scattering from a perfect electromagnetic conducting (PEMC) strip buried under a planar dielectric interface. Mediums occupying half spaces on both sides of the dielectric interface are non-integer dimensional in direction normal to the dielectric interface. Far zone scattered field, which takes into account asymptotic contributions of all multiple interaction between the strip and the dielectric interface, has been derived for a special case when half space hosting the strip is of integer dimension. Results for limiting cases of the strip have also been obtained for verification.

Kobayashi potential method has been used to study the scattering of electromagnetic plane wave from a perfect electric conducting (PEC) strip placed at planar interface of the free space and dielectric-magnetic medium. The strip has been assumed to be thicker than the skin depth and also, it is thinner than a tenth of the free-space wavelength. Furthermore, it has been assumed that dielectric-magnetic medium is homogeneous, lossy and dispersive. Lorentz-Drude model has been used to incorporate losses and dispersion both in permittivity and permeability of the dielectric-magnetic medium. Depending upon the frequency, the lossy dispersive dielectric-magnetic medium may behave as ENG Re ( ϵ ) 0 , MNG Re ( μ ) 0 , DNG Re ( ϵ , μ ) 0 , and DPS Re ( ϵ , μ ) > 0 . Scattered field pattern was observed at different operating frequencies by varying different parameters of the considered geometry. The monostatic and bistatic scattering widths were studied by varying angle of incidence, size of the strip and number of iterations. It was observed that losses become more effective in case of free space–DPS interface as compared to other cases for the interface. Minimum value of the main lobe of scattering widths was produced when the strip was placed on free space–DPS interface.

In present paper, solutions for the transverse magnetic modes propagating in a non-integer dimensional (NID) dielectric slab waveguide have been derived. Medium within the slab is NID in direction normal to the dielectric interfaces of the slab. Transcendental equations in terms of non-integer order Hankel functions have been derived. The order of non-integer order Hankel functions depends on parameter describing dimension of the NID space. Using graphical treatment, it has been shown that behavior of propagating mode changes substantially when value of the parameter describing dimension of the NID space changes. It has also been noted that NID parameter significantly effects the value of propagation constant, attenuation constant and cutoff frequency. The classical results have also been recovered when dimension of the NID slab has been taken equal to the dimension of the medium surrounding the slab.

Reflection and transmission properties of a planar interface of two non-integer dimensional (NID) half spaces are studied. It is assumed that dimensions of both half spaces normal to the interface are non-integer. Both half spaces are distinguished from each other by non integer dimensions rather than wavenumbers. A plane wave has been taken as source of excitation. It is observed that non integer dimensions are also the factors controlling the reflection and transmission properties of the interface. Special cases are also considered when one or neither of the two half-spaces are NID.