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Additive manufacturing (AM) is a fast-growing technology that supports the rapid fabrication of prototypes. Already, employing AM technologies in early product development stages can help to accelerate the time from conceptualisation phase to the market entry. Furthermore, advances in the field of materials, such as highly transparent resins in the visible wavelength spectrum, also open application potentials for the design and fabrication of optical components. Three highly transparent resins from different suppliers are studied in this work regarding their influence on the geometrical and optical properties of additively manufactured components. The different materials were processed using a masked stereolithography 3D printer. Geometrical and optical properties of the generated test samples were analysed by means of laser scanning microscopy and spectrophotometry, respectively. A clear correlation between optical properties of the resin and the solidified samples was identified. It was further found that while spin coating does not significantly affect the geometrical properties, a strong influence on the resulting optical properties could be observed. The highest transmission properties, in the range of up to 90%, were determined for samples that were spin-coated on both surfaces. Thus, applying a spin coating operation to additively manufactured optical components is recommended for the highest transmission properties. [ABSTRACT FROM AUTHOR]

In this contribution, we address quantum transport in long periodic arrays whose basic cells, localized potentials U (x) , display certain particular features. We investigate under which conditions these "local" special characteristics can influence the tunneling behavior through the full structure. As the building blocks, we consider two types of U (x) s: combinations of either Pöschl–Teller, U 0 / cosh 2 [ α x ] , potentials (for which the reflection and transmission coefficients are known analytically) or Gaussian-shaped potentials. For the latter, we employ an improved potential slicing procedure using basic barriers, like rectangular, triangular and trapezoidal, to approximate U (x) and thus obtain its scattering amplitudes. By means of a recently derived method, we discuss scattering along lattices composed of a number, N, of these U (x) s. We find that near-resonance energies of an isolated U (x) do impact the corresponding energy bands in the limit of very large Ns, but only when the cell is spatially asymmetric. Then, there is a very narrow opening (defect or rip) in the system conduction quasi-band, corresponding to the energy of the U (x) quasi-state. Also, for specific U 0 's of a single Pöschl–Teller well, one has 100% transmission for any incident E > 0 . For the U (x) parameters rather close to such a condition, the associated array leads to a kind of "reflection comb" for large Ns; | T N (k) | 2 is not close to one only at very specific values of k, when | T N | 2 ≈ 0 . Finally, the examples here—illustrating how the anomalous transport comportment in finite but long lattices can be inherited from certain singular aspects of the U (x) s—are briefly discussed in the context of known effects in the literature, notably for lattices with asymmetric cells. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) is a fast-growing technology that supports the rapid fabrication of prototypes. Already, employing AM technologies in early product development stages can help to accelerate the time from conceptualisation phase to the market entry. Furthermore, advances in the field of materials, such as highly transparent resins in the visible wavelength spectrum, also open application potentials for the design and fabrication of optical components. Three highly transparent resins from different suppliers are studied in this work regarding their influence on the geometrical and optical properties of additively manufactured components. The different materials were processed using a masked stereolithography 3D printer. Geometrical and optical properties of the generated test samples were analysed by means of laser scanning microscopy and spectrophotometry, respectively. A clear correlation between optical properties of the resin and the solidified samples was identified. It was further found that while spin coating does not significantly affect the geometrical properties, a strong influence on the resulting optical properties could be observed. The highest transmission properties, in the range of up to 90%, were determined for samples that were spin-coated on both surfaces. Thus, applying a spin coating operation to additively manufactured optical components is recommended for the highest transmission properties.

In this paper, the singular transmission properties of electromagnetic waves in one-dimensional PT-symmetric triangular finite periodic optical waveguide networks are investigated. We find that the transmission properties of electromagnetic waves differ significantly depending on whether the imaginary part of the system’s Bloch phase is zero or non-zero. Based on this, the generalized passbands and bandgaps of the PT-symmetric optical waveguide network are defined, and its generalized band structure is presented. Furthermore, we discover that electromagnetic waves incident within the frequency range of generalized bandgaps, where transmittance approaches zero, exhibit a reciprocal relationship between left and right reflectance. The system can generate interesting phenomena such as bidirectional total reflection, unidirectional super reflection, and unidirectional no reflection at these frequencies. It is also demonstrated that the frequency positions of these phenomena can be flexibly controlled by adjusting the length of the PT-symmetric waveguide and the imaginary part of its refractive index. These research findings offer a scientific basis for developing highly sensitive and multifunctional optical filters and laser reflectors.

We report the gamma-ray shielding properties, transmission factors and, effective removal cross section values of several aluminoborosilicate glasses that have been synthesized through various glass-forming materials such as Al 2 O 3 , B 2 O 3 , SiO 2 , and ZrO 2. The study utilized the elemental compositions and densities of eight different glass samples as input variables in theoretical calculations and Monte Carlo simulations. According to the results obtained, it was seen that the network-forming type used in aluminoborosilicate glasses had a direct effect on the radiation absorption properties of the glasses. The utilization of ZrO 2 and Cs 2 O at the highest concentration as the network former and glass network modifier in the NCBZ-6 sample yielded the most advantageous results in relation to its gamma-ray absorption capabilities. The benefit is intrinsically related to the heightened density of glass and the incorporation of compounds with increased atomic numbers, both of which are fundamental characteristics desired in materials designed for the purpose of gamma-ray absorption. However, the enhanced capability of ZrO 2 to absorb gamma-rays excludes the absorption of high-energy neutrons. The absence of boron trioxide (B 2 O 3) in the NCBZ-6 sample can be ascribed to its restricted availability against fast neutrons. The continued existence of ZrO 2 as a network forming in the investigated ABS glasses is likely to result in improved material homogeneity and progressive enhancement of gamma-ray absorption characteristics. It can be concluded that the incorporation of ZrO 2 as a network-former component may be an appropriate strategy to enhance the gamma-ray shielding capabilities of aluminoborosilicate glasses. [ABSTRACT FROM AUTHOR]

The object of the presented paper is to demonstrate the possibility of equalizing the transmission properties of networks described by graphs with an equal number of nodes of the same degree but differing in diameter and average path length. A node of a graph is understood to be a specialised device performing commutation and transmission functions, while an edge is understood to be a transmission link. It was assumed that this alignment can be achieved by controlling the transmission resources assigned to specific edges of a graph through which the network nodes communicate with each other. The concept of transmission resource, counted in contractual units, is understood as, for example, the number of time slots or the bandwidth of the links used to transmit information. The authors show that with the proposed method, the equalization of the mentioned network properties is achieved with a minimal increase in the global resources used for transmission. [ABSTRACT FROM AUTHOR]

Sea spray particles are a type of non-uniform, non-spherical, non-isotropic, and complex medium, and the study of the transmission characteristics of polarized light in a real sea spray environment can provide reference values in many fields, such as polarization imaging, marine target detection, and LiDAR, which can make up for the vacancy of polarized light transmission in a complex sea spray environment. In this paper, a real sea fog test is carried out in the Qingdao Sea area of China in the horizontal/oblique direction, and a platform for generating and detecting polarized light with multiple tilt angles is constructed by using the active test method, which realizes the test scheme for the characteristics of energy change and polarization state change in the linearly polarized light and circularly polarized light at different visibility levels in sea fog environments. The results show that it is more difficult to deflect the circularly polarized light than linearly polarized light at the same sea spray visibility level. With the increase in the tilt angle, a decrease in the polarization is observed. The polarization of the near-infrared light is always larger than that of the visible light, which indicates that the circularly polarized light has better polarization preservation than the linearly polarized light and the polarization preservation of the near-infrared light is better than that of the visible light.

The paper presents a simulation-based study of the impact of transmission resource reallocation on the performance of a communication network. The study considers the unevenness coefficients use to control network resources allocation. The results show that adjusting the transmission resource allocation based on the above-mentioned parameter can significantly improve network performance, leading to a equalization of network characteristics, and all of this without increasing the resources pool. The study's findings provide valuable insights for network designers and operators seeking to optimize network performance in communication systems. [ABSTRACT FROM AUTHOR]

In the present work, the optical transmission properties of a symmetric ternary periodic structure, made of superconductor and dielectric materials, are studied by using the transfer matrix method. To design a one-dimensional symmetric ternary photonic crystal, we have considered a superconductor of Bismuth strontium calcium copper oxide (BSSCO) along with silica (SiO2) and silicon (Si) as dielectric materials that are in shapes of nanolayered films. We investigate the effects of the operating temperature, number of layers, and angle of incidence on the width of the enlarged photonic bandgap obtained in the visible range, and also on the peak position of the defect mode lying in the gap, which is attributed to the symmetry in the periodic structure. It is noted that that the defect mode peak position with transmission ≈ 100% shows red-shift, and the forbidden gap slightly increases with increase in the superconductor temperature. Furthermore, the defect mode shows minor red-shift with increase in the number of unit cells, where there is a decrease in the enlarged photonic bandgap width. With an increase in the incident angle, the enlarged bandgap width decreases, and the defect mode peak position exhibits blue-shifts in both cases of transverse eclectic (TE) and transverse magnetic (TM) modes. Such kind of tunablity is more dominant for TM wave as compared to TE wave. Therefore, the present analysis based on the bandgap and defect mode tunability can be exploited in designing temperature-sensitive mirrors, monochromators optical filters, and tunable visible range devices like solar cells. [ABSTRACT FROM AUTHOR]

Recently, the vibration induced by viaduct rail transit has become a severe problem during train operation. To investigate the transmission properties of the vibration energy of the viaduct track, the procedures of transmission and dissipation of the vibration energy are analyzed based on the power flow theory of single-stage and multi-stage vibration isolation system. A viaduct track finite element (FE) model is developed, and the accuracy of the model is verified by observational acceleration. Combined with the FE model and power flow theory, the transmission and distribution characteristics of energy in the viaduct tracks are analyzed. The results show that the peak value of the vibration power is reached at the natural frequency of the track structure; the vibration energy decreases from top to bottom of the track structure in the frequency range of 1 ~ 1 000 Hz; the fastener system significantly consumes high-frequency (100 ~ 1 000 Hz) vibration energy and low-frequency (1 ~ 100 Hz) vibration energy is significantly consumed by the support of the track slab; the power flow index can indicate the transmission, distribution, and dissipation properties of the energy; and optimal vibration reduction effect can be obtained by designing the stiffness and damping of the fastener system and the support of the track slab. [ABSTRACT FROM AUTHOR]

A hybrid plasmonic waveguide structure composed of graphene-coated nanotube with a dielectric substrate is proposed in this paper. Transmission properties of the fundamental mode are studied by the finite element method (FEM). The results reveal that the mode transmission properties are greatly dependent on the nanotube radius and internal–external diameter ratio, gap distance, nanotube permittivity, as well as chemical potential of graphene. Meanwhile, it is compared with the graphene-coated nanowires with a dielectric substrate (Hajati and Hajati in Plasmonics, 2018. https://doi.org/10.1007/s11468-017-0524-2). By optimizing the parameters, the structure could achieve long-range propagation with the propagation length about 12.56 um. Moreover, it could realize deep-subwavelength confinement with the normalized mode area only ~ 10–7 in the mid-infrared (mid-IR). This structure may offer a certain theoretical basis for integrated nanophotonic devices to achieve long-distance transmission in the deep-subwavelength range. [ABSTRACT FROM AUTHOR]

A one-dimensional phononic crystal model based on Galois structure is proposed. The transmission coefficients of the elastic waves are numerically calculated and compared with those of the periodical structure. Band gaps are found and the results show that if the number of medium layers is small, the frequency range of the band gap in the Galois structure and periodic structure is basically the same. However, with the increase of the number of medium layers, the frequency range of the band gap in the Galois structure increases, and the localized resonant modes appear in the band gap. The study of transmission properties of Galois structures is helpful to understand the propagation properties of classical elastic waves in aperiodic composite structures. [ABSTRACT FROM AUTHOR]

Abstract Current classifications of sporadic Creutzfeldt–Jakob disease (sCJD) identify five subtypes associated with different disease phenotypes. Most of these histopathological phenotypes (histotypes) co-distribute with distinct pairings of methionine (M)/valine (V) genotypes at codon 129 of the prion protein (PrP) gene and the type (1 or 2) of the disease-associated PrP (PrPD). Types 1 and 2 are defined by the molecular mass (~ 21 kDa and ~ 19 kDa, respectively) of the unglycosylated isoform of the proteinase K-resistant PrPD (resPrPD). We recently reported that the sCJDVV1 subtype (129VV homozygosity paired with PrPD type 1, T1) shows an electrophoretic profile where the resPrPD unglycosylated isoform is characterized by either one of two single bands of ~ 20 kDa (T120) and ~ 21 kDa (T121), or a doublet of ~ 21–20 kDa (T121−20). We also showed that T120 and T121 in sCJDVV have different conformational features but are associated with indistinguishable histotypes. The presence of three distinct molecular profiles of T1 is unique and raises the issue as to whether T120 and T121 represent distinct prion strains. To answer this question, brain homogenates from sCJDVV cases harboring each of the three resPrPD profiles, were inoculated to transgenic (Tg) mice expressing the human PrP-129M or PrP-129V genotypes. We found that T120 and T121 were faithfully replicated in Tg129V mice. Electrophoretic profile and incubation period of mice challenged with T121−20 resembled those of mice inoculated with T121 and T120, respectively. As in sCJDVV1, Tg129V mice challenged with T121 and T120 generated virtually undistinguishable histotypes. In Tg129M mice, T121 was not replicated while T120 and T121−20 generated a ~ 21–20 kDa doublet after lengthier incubation periods. On second passage, Tg129M mice incubation periods and regional PrP accumulation significantly differed in T120 and T121−20 challenged mice. Combined, these data indicate that T121 and T120 resPrPD represent distinct human prion strains associated with partially overlapping histotypes.

The transmission and reflection properties of magnetostatic biased graphene layers are investigated based on analytical method, where graphene is treated as a bulk material. Considering the anisotropic nature of the magnetostatic biased graphene (magnetized graphene), the generalized reflection and transmission coefficients of a plane wave incidence on anisotropic multilayer structures are first derived. The accuracy of this method is validated by a numerical example of a plane wave incidence on a magnetized monolayer graphene in free space. Based on this model, the transmission coefficient decreases with increasing the incident angle for the TE (transverse electric) polarized wave incidence, while an opposite phenomenon occurs for the TM (transverse magnetic) polarized wave incidence. The transmission properties can be also modulated by changing the external static magnetic field. The electromagnetic propagation properties of composites consisting of magnetized graphene and dielectric layers are also analyzed based on this method. The transmission properties degrade with increasing the number of magnetized graphene layers.

Current classifications of sporadic Creutzfeldt–Jakob disease (sCJD) identify five subtypes associated with different disease phenotypes. Most of these histopathological phenotypes (histotypes) co-distribute with distinct pairings of methionine (M)/valine (V) genotypes at codon 129 of the prion protein (PrP) gene and the type (1 or 2) of the disease-associated PrP (PrPD). Types 1 and 2 are defined by the molecular mass (~ 21 kDa and ~ 19 kDa, respectively) of the unglycosylated isoform of the proteinase K-resistant PrPD (resPrPD). We recently reported that the sCJDVV1 subtype (129VV homozygosity paired with PrPD type 1, T1) shows an electrophoretic profile where the resPrPD unglycosylated isoform is characterized by either one of two single bands of ~ 20 kDa (T120) and ~ 21 kDa (T121), or a doublet of ~ 21–20 kDa (T121−20). We also showed that T120 and T121 in sCJDVV have different conformational features but are associated with indistinguishable histotypes. The presence of three distinct molecular profiles of T1 is unique and raises the issue as to whether T120 and T121 represent distinct prion strains. To answer this question, brain homogenates from sCJDVV cases harboring each of the three resPrPD profiles, were inoculated to transgenic (Tg) mice expressing the human PrP-129M or PrP-129V genotypes. We found that T120 and T121 were faithfully replicated in Tg129V mice. Electrophoretic profile and incubation period of mice challenged with T121−20 resembled those of mice inoculated with T121 and T120, respectively. As in sCJDVV1, Tg129V mice challenged with T121 and T120 generated virtually undistinguishable histotypes. In Tg129M mice, T121 was not replicated while T120 and T121−20 generated a ~ 21–20 kDa doublet after lengthier incubation periods. On second passage, Tg129M mice incubation periods and regional PrP accumulation significantly differed in T120 and T121−20 challenged mice. Combined, these data indicate that T121 and T120 resPrPD represent distinct human prion strains associated with partially overlapping histotypes. [ABSTRACT FROM AUTHOR]

Selective laser melting is a promising additive manufacturing technology for manufacturing porous metallic bone scaffolds. Bone repair requires scaffolds that meet various mechanical and biological requirements. This paper addresses this challenge by comprehensively studying the performance of porous scaffolds. The main novelty is exploring scaffolds with different porosities, verifying various aspects of their performance and revealing the effect of their permeability on cell growth. This study evaluates the manufacturability, mechanical behaviour, permeability and biocompatibility of gyroid scaffolds. In simulations, mechanical behaviour and permeability exhibited up to 56% and 73% accuracy, respectively, compared to the experimental data. The compression and permeability experiments showed that the elastic modulus and the permeability of the scaffolds were both in the range of human bones. The morphological experiment showed that manufacturing accuracy increased with greater designed porosity, while the in vitro experiments revealed that permeability played the main role in cell proliferation. The significance of this work is improving the understanding of the effect of design parameters on the mechanical properties, permeability and cell growth of the scaffolds, which will enable the design of porous bone scaffolds with better bone-repair effects.

The present study aims at investigating the influence of yarn structure, modified through process parameters of ring frame (spindle speed, twist multiplier and ring frame draft), on low-stress mechanical, thermal properties and transmission properties of fabric. It is observed that the structural changes influence thermal, transmission and low-stress mechanical characteristics of fabrics due to change in fabric porosity and thickness. In general, the bending and compression properties increase but shear and surface properties of the fabrics decrease with the increase in spindle speed, twist multiplier and draft. The study further reveals that air permeability, thermal absorptivity, thermal diffusivity, heat conductivity and moisture transmission properties increase but thermal resistance decreases with the increase in spinning process parameters. [ABSTRACT FROM AUTHOR]

In this paper, the singular transmission properties of electromagnetic waves in one-dimensional PT -symmetric triangular finite periodic optical waveguide networks are investigated. We find that the transmission properties of electromagnetic waves differ significantly depending on whether the imaginary part of the system's Bloch phase is zero or non-zero. Based on this, the generalized passbands and bandgaps of the PT -symmetric optical waveguide network are defined, and its generalized band structure is presented. Furthermore, we discover that electromagnetic waves incident within the frequency range of generalized bandgaps, where transmittance approaches zero, exhibit a reciprocal relationship between left and right reflectance. The system can generate interesting phenomena such as bidirectional total reflection, unidirectional super reflection, and unidirectional no reflection at these frequencies. It is also demonstrated that the frequency positions of these phenomena can be flexibly controlled by adjusting the length of the PT -symmetric waveguide and the imaginary part of its refractive index. These research findings offer a scientific basis for developing highly sensitive and multifunctional optical filters and laser reflectors. • Electromagnetic waves in PT-symmetric optical waveguides show distinct propagation properties based on the imaginary part of the Bloch phase. • Extended definitions of passbands and bandgaps in PT-symmetric optical waveguides with a detailed band structure diagram provided. • PT-symmetric optical waveguides achieve bidirectional total and unidirectional super reflections with opposite direction no reflection at arbitrary frequencies. [ABSTRACT FROM AUTHOR]

In this paper, a new type of plasmonic waveguide consisting of two vertically coupled double-graphene-coated nanowires integrated with a thin high-index dielectric substrate is designed. The transmission properties of the surface plasmon polaritons supported by the waveguide are investigated by the finite element method (FEM). Theoretical investigations reveal that deep-subwavelength mode confinement as well as long-range propagation length can be achieved simultaneously in the studied structure through optimizing the geometric and electromagnetic parameters. The comparisons of the mode properties between the proposed waveguide and waveguides studied in the published literatures are also considered. This structure has potential applications in ultra-tight optical integration field. [ABSTRACT FROM AUTHOR]

Abstract The properties of light localization in finite one-dimensional photonic heterostructures composed of alternating layers of graphite and wurtzite GaN are studied theoretically. Results are obtained within the transfer-matrix formalism for both transversal-magnetic and transversal-electric polarizations of the incident electromagnetic wave in the infrared region of the electromagnetic spectrum. A structural disorder is introduced into the system by assuming that the width of the slabs in the heterostructure may randomly fluctuate around its mean value. For oblique incidence and transversal-magnetic polarization, a coupling of the infrared photon modes with the longitudinal optical phonons is discussed. This photon–phonon coupling gives rise to signatures of the phonon-polariton modes in the transmission and localization properties of the system, which are observed in the cases of low and moderate levels of structural disorder. The dependence of the properties of the light localization on the number of graphite-GaN double layers is also analyzed. Highlights • Light localization properties of graphite-GaN heterostructures are investigated. • The width of each layer may randomly fluctuate around its mean value. • A coupling of light and LO phonons is observed in the TM configuration. • Delocalized states are obtained in the case of weak disorder and in spite of absorption. • Phonon-polariton modes are very sensitive to a change in the number of layers. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present an analytical method to quantitatively address the influence of a focusing illumination on the optical response properties of a metasurface illuminated by a finite-size beam. Most theoretical and numerical studies are performed by considering an infinite periodic structure illuminated by a plane wave. In practice, one deals with a finite-size illumination and structure. The combination of the angular spectrum expansion with a monomodal modal method is used to determine the beam size needed to acquire efficient properties of a metasurface that behaves as an anisotropic plate. Interesting results show that the beam-size can be as small as 5 × 5 periods to recover the results of a plane wave. Other results also show that the beam-size can be used as an extrinsic parameter to enhance the anisotropic metasurface performance and to adjust its expected properties finely (birefringence and/or transmission coefficient). These findings are important for the design of real (finite) structures and can be adapted for experimental conditions to achieve optimized results and take full advantage of the metamaterial properties. [ABSTRACT FROM AUTHOR]

Fabrics produced by weaving or knitting techniques essentially comprise of threads and air spaces and its proportion is dependent on several factors including the interlacement pattern; known as weave in case of woven fabrics. This air space is responsible for imparling breathability to the fabric; more the air space (open fabric construction) more is the breathability and hence preferred as summer wear. This paper gives the evaluation of transmission properties of fabric woven with plain and its derived weaves. [ABSTRACT FROM AUTHOR]

This work reports fabrication and characterization of Film Bulk Acoustic Resonator (FBAR) to improve the performance characteristics for RF filter and sensing application. Zinc oxide as a piezoelectric (PZE) material was deposited on an aluminum bottom electrode using an RF magnetron sputtering, at room temperature, and gold as top electrode for the resonator. Tetramethyl ammonium hydroxide (TMAH) setup was used for bulk silicon etching to make back side cavity to confine the acoustic signals. The transmission characteristics show that the FBARs have a central frequency at 1.77 GHz with a return loss of −10.7 dB. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present an analytical method to quantitatively address the influence of a focusing illumination on the optical response properties of a metasurface illuminated by a finite-size beam. Most theoretical and numerical studies are performed by considering an infinite periodic structure illuminated by a plane wave. In practice, one deals with a finite-size illumination and structure. The combination of the angular spectrum expansion with a monomodal modal method is used to determine the beam size needed to acquire efficient properties of a metasurface that behaves as an anisotropic plate. Interesting results show that the beam-size can be as small as 5 × 5 periods to recover the results of a plane wave. Other results also show that the beam-size can be used as an extrinsic parameter to enhance the anisotropic metasurface performance and to adjust its expected properties finely (birefringence and/or transmission coefficient). These findings are important for the design of real (finite) structures and can be adapted for experimental conditions to achieve optimized results and take full advantage of the metamaterial properties.

In this paper, an asymmetric plasmonic waveguide structure is designed with a MIM waveguide and an oblique rectangular cavity, and its double Fano resonance characteristics and transmission properties are numerically investigated by the finite element method. The results show that double Fano resonances appear in the transmission spectra when the oblique rectangular cavity has different rotation angular θ . The double Fano resonances derive from different mechanisms, one of Fano resonances is induced by the interaction of horizontal and vertical resonance modes in the rectangular cavity, and the other is derived from rotating the rectangular cavity. So the Fano resonances can be easily tuned by the changing angle of rotation θ and structure parameters of rectangular cavity. Moreover, when the rectangular cavity is rotated to a certain angle, three Fano resonant peaks are appeared in the transmission spectra. The asymmetric plasmonic structure is also to detect the refractive index changes of the filled media inside of rectangular cavity and waveguide, which reveals a potential sensors application of the MIM waveguide with oblique rectangular cavity. [ABSTRACT FROM AUTHOR]

A theoretical study of one-dimensional heterostructures composed of alternate layers of a Kerr polaritonic material and a linear dispersive metamaterial is performed. For frequency values at the edges of the non-Bragg zero- ϕ eff gap of the heterostructure in the linear regime, a switching from very low to high transmission states is obtained and localized gap solitons of various orders are found, depending on the particular value of the incident power. Soliton solutions are shown to be robust with respect to absorption effects and a study is presented for gap soliton phases at the top and bottom of the zero- ϕ eff gap in the case of defocusing and focusing nonlinearities. [ABSTRACT FROM AUTHOR]

The localization properties of electromagnetic waves in one-dimensional disordered nonlinear-Kerr/metamaterial heterostructures are investigated. Structural disorder is introduced via a random fluctuation of layer widths of both nonlinear-Kerr and metamaterial slabs composing the photonic heterostructure. For frequency values in the vicinity of the zero− n gap, multiple electromagnetic modes with different transmission lengths are obtained for a given value of the Kerr defocusing nonlinearity power. Maximum-delocalized photonic states, which are associated with high-transmission electromagnetic modes corresponding to gap-soliton waves, are found to be quite sensitive with respect to the degree of disorder. Moreover, we have found that inclusion of absorption effects leads, as expected, to a decreasing of the transmission length. [ABSTRACT FROM AUTHOR]