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Metamaterials are so-named to recognize and emphasize their purpose, which is to achieve material performance beyond the limitations of conventional composites. The holy grail of conventional composite design is to achieve an optimum combination of the constituent's properties without requiring that they react. Success is measured by how close the composite properties are to a volumetric average of those of its constituents. One of the goals of this paper is to outline the strategy of metamaterial design, its hallmark being the exploitation of low dimensional phenomena to extend composite performance. Another is to discuss the generality of the metamaterial strategy, and to illustrate its successful implementation in diverse application areas. It is also shown that ideal electromagnetic composite responses cannot be achieved by implementing designs based on utilizing the prevalent effective media theories. More disturbing is the observation that the deviation of the composite response from the ideal is greatest when the disparity of the constituent properties is largest. Unfortunately, this is the situation of most interest, where a volumetrically averaged response has the greatest practical value. This response can be achieved, however, by utilizing electromagnetic metamaterials design. The rules for this approach are illustrated by the successful design of a laminated electromagnetic composite that possesses some remarkable, and previously unattainable properties.
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Macroscopic dielectric and piezoelectric properties are strongly influenced by structural features that span a wide variety of length scales in ferroelectric based materials. This paper will address a number of examples of such features in important materials that are presently being developed for next generation capacitor devices and/or piezoelectric sensors or actuators. Special emphasis will be given to the interrelationship of crystal structure, crystal chemistry, phase transition, and properties in perovskite crystal structures which can host ferroic behavior. This ferroic behavior includes ferroelectric, antiferroelectric, and ferroelastic transitions. Transmission electron microscopy techniques will be used to demonstrate and characterize the detailed structure of the ferroelectric in which dielectric and piezoelectric properties emerge.
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The goal of the polarimetry of electromagnetic solids is the thorough determinations of not only the linear and circular birefringences (LB an CB) but also the linear and circular dichroisms (LD and CD). Needless to say, measurements of circular phenomena are exceedingly more difficult than those of linear ones. For instance, the long period of 170 years elapsed from the discovery of CB by Arago in 1811 until the development of high accuracy universal polarimeter (HAUP) by Kobayashi in 1983, when the first perfect measurements of CB of solids became possible. Subsequent to the appearance of the HAUP method, attempts of extending HAUP theory to be applicable to CD measurements were followed by Moxon and Renshaw, and Dijkstra, Kremers, and Meekes by using Jones matrix calculus. However, their measurements to NiSO4 multiplied by 6H2O were not fully satisfactory. We completed afresh the theory of the extended HAUP and measured successfully LD of a high temperature superconductor Bi2Sr2CaCu2O8. An important fact was clarified; the extended HAUP theory indicates that CD can be obtained exclusively through accurate measurements of (theta) 0, a characteristic angle introduced in the original HAUP method. It means that there would be no ways for measuring CD of solids except for the HAUP method. Preliminary results of applying our theory to silver thiogallate are shown finally.
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Optical fibers have almost unlimited capacity, but cannot address the users desire for mobility and ubiquitous access. The synergy of these two worlds can be seen in the direction of the Radio-over-Fiber. This paper presents to the reader an introduction for the mobile radio channel - basic physical phenomena, their implications on the transmitted signal, and how the radio channels are modeled. Special attention is given to the small-scale effects, such as multipath, and Rayleigh and Rice distributions of received signal, as these dominate in the case of indoor communication systems.
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If a metal surface has a roughness of a few nanometers, an incident light wave may excite the surface waves known as surface plasmon polaritons. In turn, the plasmon polaritons may themselves be outwardly surface-coupled to produce effects in the light escaping from the surface. Here, the polariton-related effects in both the fundamental and second-harmonic emitted light are considered. In the linear case, a theoretical approach is developed that allows the polaritons to be scattered several times within the surface before coupling to diffuse light escaping from the surface. In the diffuse scatter emitted by a randomly rough surface, these high-order processes are shown to produce changes in the shape and width of the backscattering peak. In experimental results for the emitted second-harmonic generation, it is found that the features are dominated by the contributions of polaritons at both the fundamental and harmonic frequencies. These nonlinear wave interactions are illustrated with experimental results for randomly rough and for quasiperiodic surfaces.
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Unique elastic fields, beams defined by a given set of orthonormal scalar functions on a two-dimensional or three- dimensional beam manifold, are treated. The proposed approach enables one to obtain sets of orthonormal beams and various families of localized fields in both isotropic and anisotropic solids. This can be applied also to sound beams in liquids. By way of illustration, the fields defined by the spherical harmonics are considered. The families of orthonormal beams can be used as functional bases for complex elastic fields. The obtained localized elastic fields include storms, whirls, and tornadoes, i.e., the localized fields for which time average energy flux is identically zero at all points, azimuthal, and spiral, respectively. It is shown that these fields can be combined into a complex field structure, such as an ultrasonic diffraction grating. This makes them promising tools to control laser radiation.
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The main radiation and scattering properties of cavity backed microstrip patch antennas loaded by homogeneous and inhomogeneous chiral, ferromagnetic and bianisotropic materials are investigated in this paper. The theoretical approach used is based on the variational formulation applied to a cavity filled by an arbitrary number of layers and in presence of an arbitrary number of metallizations (i.e. patches and ground planes of finite dimensions). In order to numerically solve the stationary equation for the electromagnetic field, a Finite Element Method (FEM) in conjunction with a Boundary Element Method (BEM) is applied and the main scattering and radiation features of the cavity antenna are straightforwardly carried out. Some numerical results showing the effects of different complex media on the radiation pattern, on the input impedance and on the radar cross section of multi-layered cavity antennas are, finally, presented. Such results show that chiral materials allow to reduce the antenna size for a fixed working frequency increasing, besides, the cross-polarization levels. Some bianisotropic materials, instead, allow to obtain the same size reduction as chiral media without degrading the cross-polarization purity.
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The transformation of a circularly polarized electromagnetic wave in a magnetoplasma medium with increasing plasma density is considered. The wave propagates along the static magnetic field. Complete analysis, including ion motion, is given both for slow (compared to the wave frequency) and rapid ionization rate. In the case of slow temporal variation of the plasma density, a relation between the energy of the wave and its frequency, which is conserved during the plasma creation process (adiabatic invariant), is found. The existence of significant energy losses follows from the invariant. The dissipative mechanism is explained via consideration of the case of a sudden growth of plasma density in time from one value to another. It is shown that energy transforms into the kinetic energy of carriers and preionization of the medium plays a principal role in the dissipation process. In the special case of a whistler wave, up to 50% of the energy may be transformed into ion-cyclotron wave when dense plasma is rapidly created.
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Thin film properties can be engineered by the high degree of control in many CVD and especially PVD processes. In particular, the thin film morphology often has a direct connection between preparation and property relations. This review will focus on understanding the morphology in PVD coatings prepared at low adatom mobilities where columnar thin films are prepared, with the column sizes ranging from nm- to micrometers -sizes and the columns forming hierarchical clusters of columns having a fractal-like behavior. We will discuss the effects of ion bombardments and angle of incidence of the directional vapor species with respect to the morphology origin and evolution. These various morphologies are related to applications ranging from hard coatings to optical coatings to sculptured thin films.
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Photocatalytic properties of obliquely deposited TiO2 thin films with various shaped columns were investigated. The columnar films such as zigzag, cylinder and helix were prepared by dynamic oblique deposition (DOD) method. It was found that the optimum morphology for surface photocatalytic reaction has been obtained at the deposition angle (alpha) equals 70 degrees, where the photocatalytic activity is 2.5 times larger than that at (alpha) equals 0 degrees. In addition, effective surface area was estimated by Monte Carlo simulation and quantitative agreement was obtained between theoretical and experimental results. It was concluded that the enhanced surface photocatalytic properties of obliquely deposited TiO2 films can be explained in terms of effective changes in surface area originated from morphology modified by thin film nanotechnology.
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We discuss the concept and application of a class of Sculptured Thin Films called Thin Film Helicoidal Bi- anisotropic Mediums. A new device concept is proposed through which in-line, lossless, polarization routing is possible in optoelectronic systems. Chiral/chiral reflection at the interface between optically active mediums is shown to yield negative results.
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The localized homogenization framework, the Mori-Tanaka average stress and the Eshelby tensor for ellipsoids are used to estimate the elastic constitutive properties of chiral sculptured thin films from their microstructural details. The devised model contains five arbitrary parameters, whose values can be decided upon by suitable experimentation. The responses of a chiral STF to static and dynamic loading along the axis of nonhomogeneity are presented.
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We have grown a variety of oxide nanostructures, including nanodots, nanowires, and nanorings. The growth of these structures relies on precise growth mode control and requires a special pulsed laser deposition system which can work at temperatures above 1000C and at high background oxygen pressures. The dynamics of nanostructure growth have been studied in detail. In particular, we have determined the temperatures and deposition rates necessary for growing dot or wire structures on atomically flat surfaces. The nanostructures have been successfully included in fractional-layer superlattices for easier characterization.
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A straightforward review of magnetooptics is given, emphasising both linear and nonlinear guided wave properties. A global envelope approach is discussed which describes TE-TM interactions and TE-TM vector Manakov-type spatial solitons, in the neighbourhood of wave guide inhomogeneities. The presentation is at a level such that the global method can easily account for the vector soliton dynamics and the nonreciprocity introduced by the magnetooptical influence. It is emphasised that magnetooptic waveguides have great potential in nonlinear optics and are destined to support and enhance a major change in chip technology.
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Magnetoelasticity encompasses a wide range of phenomena including, but not limited to, volume and Joule magnetostriction, the Villari effect, direct and inverse Wiedemann effects, the (Delta) E effect, and a magnetoelastic contribution to the apparent magnetic anisotropy. These effects are conveniently codified in a magnetoelastic energy density which, together with the magnetic (including exchange) and elastic energy densities, provides a consistent thermodynamic description of magnetoelasticity. In this review I shall briefly examine each of these effects and the corresponding terms of the energy density. This energy density is described by a collection of material constants which, in principle, are derivable from theory. The physical coordinates which are maintained constant in any experiment dictate the relevant combination of these material constants which is ultimately observed. Static and dynamic measurements are generally carried out with different constraints and, not surprisingly, these experiments measure different combinations of material parameters. For example, the highly magnetostrictive smart material Terfenol-D (Dy0.73Tb0.27Fe1.95) has a static magnetic anisotropy which is markedly different from the anisotropy exhibited in a dynamic measurement.
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This paper begins with an overview of nanostructured magnetoelastic materials, namely the amorphous ferromagnetic alloys, detailing how the material structure gives rise to unique magnetic and physical properties suitable for sensor applications, such as a high magnetostriction coefficient, high magnetoelastic coupling, as well as low coercive force and anisotropy field. With the correlation between the material structure and the magnetic and physical properties established, we then show how these unique properties are utilized for measuring multiple physical parameters such as stress/strain, liquid density and viscosity, fluid flow velocity, coating elasticity, ambient temperature, and chemical analyte concentrations including glucose, pH, carbon dioxide, and ammonia.
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Statistical and probabilistic methods have been frequently used to model and analyze electromagnetic scattering problems. This approach may in some cases be the most realistic one, while in others, when combined with deterministic methods, it allows to extract, from the available data, information which are otherwise difficult to obtain. The aim of this presentation is to provide an introduction to some statistically-based approaches of analysis of scattering problems, and illustrate their efficiency and limitations. A general methodology of prediction of the behavior of a complex system can thus be established which, among many advantages, allows a significant reduction of the computational cost.
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Rigorous coupled wave analysis (RCWA) approach is employed to determine electromagnetic (EM) scattering from cylindrical (circular and noncircular) spatially, inhomogeneous, anisotropic material objects. From the late 70's to the present, the RCWA approach has become an extremely important technique for the study of EM diffraction from one and two dimensional planar gratings. RCWA which is a spectral domain technique, is based on expanding Maxwell's equations in a set of Floquet harmonics, and from this expansion, arranging the unknowns of the system in a state variable (SV) form from which a solution may be found. For the study of diffraction from planar gratings, the technique has proved to be a very fast, accurate, and effective method which requires only the solution of relatively small matrix and eigenvalue equations. When the RCWA approach is applied to study scattering from two and three dimensional objects, the theta and phi azimuthal coordinates represent periodic coordinates from which Floquet harmonics may be used to expand the unknowns of the system. Secs. 1 and 2 will review the RCWA method and its application to E-mode planar diffraction gratings. Sec. 3 will present the basic RCWA EM formulation to study scattering from inhomogeneous, anisotopic circular, cylindrical objects, and Sec. 4 will briefly review the RCWA EM formulation used to study scattering from elliptical inhomogeneous objects.
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The evaluation of acoustic or electromagnetic fields induced in the interior of inhomogeneous penetrable bodies by external sources is based on well known volume integral equations; this is particularly true for bodies of arbitrary shape and/or composition, for which separation of variables fails. In this paper we focus the investigation to acoustic (scalar fields) in inhomogeneous spheres of arbitrary composition, i.e., with r-, (theta) - dependent medium parameters. The volume integral equation is solved by a hybrid (analytical - numerical) method, which takes advantage of the orthogonal properties of spherical harmonics, and, in particular, of the so-called Dini's expansions of the radial functions; the optimum convergence of the former is, also, determined. The scalar case treated here, serves as a stepping stone for the solution of the more difficult electromagnetic problem.
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Optical response of metal-dielectric inhomogeneous films is considered. The generalized Ohm's law is formulated that relates electric and magnetic fields outside to the currents inside the film. Computer simulations, with the use of the generalized Ohm's law show that the local electric and magnetic fields experience giant spatial fluctuations. The fields are localized in small spatially separated peaks: electric and magnetic hot spots. In these hot spots the local fields (both electric and magnetic) exceed the applied field by several orders of magnitude. It is also shown that transmittance of a regular modulated metal film is strongly enhanced when the incident wave is in resonance with surface polaritons in the film. A new optical switch based on this effect is proposed.
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Cermet is mixture of nano-sized metallic grains and insulating matrix. When concentration in metal is large enough, the conducting particles are strongly interacting between each other. As predicted by V. Shalaev for fractal metallic clusters and experimentally verified, in the vicinity of the percolation threshold, the local electromagnetic field can be very large because of plasmon resonance in the metallic grains which may happen in a wide spectrum of frequencies. In this enhanced field region, the micro-crystallites of the matrix are immersed in these huge fields. In the spectral range of the optical phonon of the matrix there can be a very large absorption band because of the possible coupling between phonon of the matrix and resonance of the metallic grains. We experimentally observe this huge absorption in gold alumina cermets. The theoretical model is in good agreement with experimental results.
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Periodic structures having a period shorter than the light wavelength and optically defined by a permittivity tensor field (epsilon) (r) are considered to discuss some boundary effects evidenced in chiral smectic liquid crystals by a numerical analysis. A more general approach to the problem of the boundary effects is given by considering the exact equations for the propagation of light in periodic media and making use of the coupled wave method. For structures periodic in only one direction q, the boundary effects strongly depend on the angle (theta) between q and the boundary normal v. They are related to the existence of a boundary layer where the electromagnetic field is rapidly changing, owing to the presence of surface waves strongly attenuated along v. The thickness of the layer is comparable to the crystal period for (theta) equals(pi) /2, increases by decreasing (theta) , and diverges for sin (theta) equal to n(p/(lambda) ), where n is an average refractive index. Below this value it is no more possible to separate bulk and boundary effects, and the very existence of a macroscopic model becomes questionable. More precisely, no macroscopic model is able to correctly describe the properties related to the spatial dispersion, as for instance the optical activity and the depolarized reflection. Similar considerations can be done for 2D and 3D crystals, but the surface effects are more complex because different boundary layers are associated to the different vectors q of the reciprocal lattice. The thickness of the layer depends again on the angle (theta) q between q and v, and diverges for small enough (theta) q.
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We consider the strong-property-fluctuation theory (SPFT) for linear bianisotropic mediums based on ellipsoidal distribution topology. Implementations of the SPFT are presented for three choices of the covariance function. The SPFT is then applied to estimate the effective constitutive parameters of two types of homogenised composite medium: a chiroferrite medium and a reciprocal biaxial bianisotropic medium. The influences of the component phase topology and orientation, correlation length and covariance function are explored. The SPFT estimates of the constitutive parameters are compared with those calculated using the Incremental Maxwell Garnett and the Bruggeman homogenisation formalisms.
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In this paper we explore both theoretically and experimentally the electromagnetic properties of microwave photonic band gap structures formed by several layers of doubly periodic arrays of conducting elements. The experimental results are in good agreement with the theoretical calculations. The method of the analysis of a single doubly-periodic array of conducting strips, based on Floquet theorem and the moments method, is combined with a recursive algorithm suitable to calculate the reflection and transmission operators for a system of several such layers. These structures can find practical applications in high- quality polarization-selective filters.
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Recently, much attention has been paid to novel thin artificial impedance surfaces. For applications it is important that the thickness of the layer is as small as possible. One possible realization is based on the use of quasi-bulk cells, so that the resonance is achieved in thin layers due to concentration of the fields in equivalent capacitances and inductances. However, the geometry of these layers is quite complicated (3D cells), and it is not possible to increase the surface inductance keeping the thickness small. Another possible cause for resonance response can be near reactive fields generated at inhomogeneities or cracks. In this paper we investigate a doubly periodic array of small resonant scatterers positioned close to an ideally conducting plane. It is shown, that such a structure at the frequencies near the resonance acquires a very high impedance and behaves as magnetic screen.
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Recent applications of semiconductor quantum wells to engineered nonlinear optical devices are reviewed. Two specific applications which have recently been demonstrated successfully experimentally are highlighted: patterned quasi-phase-matching gratings for 3-wave mixing in second- order nonlinear devices; quantum-well saturable absorbers and pulse shapers for ultrashort-pulse modelocking of several laser types, including solid-state and semiconductor lasers.
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We present the study of optical nonlinearities of nematic liquid crystals under the influence of an external (AC) electrical field. The Z-scan technique is employed as the experimental method to observe and monitor the nonlinear effect. The split-step method is used to model the beam propagation in the liquid crystal sample, and hence derive the far-field intensity distribution, from which the theoretical Z-scan curves are calculated.
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It is now known that plasmon oscillations supported by nanostructured metal thin films of fractal morphology, can result in large local fields and strong enhancement of optical phenomena, for example Raman scattering. The localized plasmons, acting like nano-antennas, can concentrate very large electromagnetic energy in nanometer- sized areas, hot spots, and provide particularly strong enhancement of optical responses, in a very broad spectral range. Our new experimental results show up position dependence of the hot spots on the polarization state of the light. Moreover as expected from recent theoretical predictions, on this kind of thin percolating films, there is a dramatic enhancement of the second harmonic generation (2(omega) ) out of the specular directions. This unusual diffuse SHG could be connected to possible chirality of the percolating metallic films, which is expected to manifest itself as change in the hot-spot distribution for the left and right circularly polarized incident light.
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Both in natural photosynthetic systems and also their molecularly engineered mimics, energy is generally transferred to the sites of its chemical storage from other sites of primary optical excitation. This migration process generally entails a number of steps, frequently involving intermediary chromophore units, with each step characterised by high efficiency and rapidity. Energy thereby accrues at reaction centres where its chemical storage occurs. At high levels of irradiation, energy harvesting material can exhibit novel forms of optical nonlinearity. Such behaviour is associated with the direct pooling of excitation energy, enabling secondary acceptors to undergo transitions to states whose energy equals that of two or more input photons, subject to decay losses. Observations of this kind have now been made on a variety of materials, ranging from photoactive dyes, through fullerene derivatives, to lanthanide doped crystals. Recently developed theory has established the underlying principles and links between the modes of operation of these systems. Key factors include the chromophore layout and geometry, electronic structure and optical selection rules. Mesoscopic symmetry, especially in photosynthetic pigment arrays and also in their dendrimeric mimics, is here linked to the transient establishment of excitons. The involvement of excitons in energy harvesting is nonetheless substantially compromised by local disorder. The interplay of these factors in photoactive materials design is discussed in the context of new materials for operation with intense laser light.
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A simple electromagnetic medium is described by the constitutive relations D = ε E,B = μ H,J = σ E, where all the electromagnetic parameters, the permittivity ε, the permeability μ , and the conductivity σ are scalar constants. All other electromagnetic mediums are complex mediums. A sub-class of complex mediums are layered mediums which are piece-wise simple mediums. Each layer is a simple medium with scalar electromagnetic parameters. Availability of commercial software for electromagnetic simulation justifies reduction of time spent in teaching the mathematics of special functions in electromagnetic core course at the graduate level. However to make effective use of these packages, the ability to relate the dominant effect of each kind of a geometrical feature and the dominant effect of each kind of complexity in the medium properties could be important in interpreting the results and also to find out when the package did not give correct results. The course outline of a departmental core course in 'Electromagnetic Waves and Materials' at our university, which includes dispersive medium, anisotropic medium, chiral medium, periodic medium, superconducting medium and their applications in the areas of microwaves and optics will be presented. Extension of the system theory to the systems where the basic elements are complex mediums of various kinds is a challenging research area.
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The form of macroscopic physical property tensors of a crystalline structure can be determined from its magnetic or non-magnetic point group symmetry. In a ferroic crystal containing two or more equally stable domains of the same structure but of different spatial orientation, macroscopic tensorial physical properties that are different in domains, provide a tensor distinction of the domains. The use of point group symmetries in this tensor distinction is reviewed in this paper: Point group symmetry based classifications of domains have been defined to determine if specific macroscopic tensorial physical properties can provide a tensor distinction of all or some domains which arise in a phase transition. For pairs of domains, the tensor distinction is determined from a point group symmetry relationship, called a twin law. Recent work on domain average engineering in ferroics which focuses on the averaged point group symmetry and averaged physical properties of subsets of domains is also discussed.
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Recently a general framework has been proposed for constitutive relations. This theoretical approach attempted to represent constitutive relations as spatiotemporal differential operators acting on the physically observable fields. The general statement is sufficiently broad to embrace linear and nonlinear systems, and dispersive as well as inhomogeneous systems. The present study investigates specific examples related to polarizable and chiral media. It was immediately realized that prior to working out the examples, we have to better understand the relation of the kinematics of particles to field concepts. Throughout, the Minkowski space notation and related relativistic ideas are exploited for simpler notation and deeper understanding. The present is an overview, the full-size version is indicated below.
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The linearly polarized laser beam becomes elliptically polarized when it passes through the quartz cube in directions different to the optical axis. Such phenomenon is explained with the interaction of two orthogonally polarized waves where one is ordinary and the other is extraordinary that are spread in one and the same direction within the crystal. The research of the polarization change of the laser beam polarized under 45 degree(s) angle after it was passed through the quartz cube at different angles of the light falling onto the cube facet and therefore for different crystallographic directions is presented in the given work. It is revealed that the character of the elliptical polarization change differs sharply for two directions parallel and perpendicular to the optical axis. The measurements were carried out with the pure colorless quartz. It is revealed that the ellipse transformation has a slightly unexpected character both for one and the other directions and differs from the usual behavior described in the literature.
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Detailed refractive indices measurements of transparent LiNbO3, LiTaO3 and (Ba,Na)NbO3 crystals in the temperature region 20-700 degree(s)C are reported. It is obtained that, besides the similarity in chemical compound and structure, optical properties of these crystals are different. The important common feature of lithium niobate and lithium tantalate crystal is dispersion of thermooptical coefficients. It is shown that phase transitions with different character take place at approximately 600 degree(s) in all measured crystals. Phase transitions are accompanied by such optical appearances as diffraction and coexistence of phases.
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Silicon carbonitride films were synthesized by RP CVD process using the novel single-source precursor that is derivative of 1,1-dimethylhydrazine, (CH3)2HSiNHN(CH3)2. The films were characterized by X- ray photoelectron (XPS), infrared (FTIR) and ultraviolet (UV) spectroscopy. The microstructure of the films was examined by scanning electron microscopy (SEM) and diffraction of synchrotron radiation (DSR) methods. XPS and FT-IR spectroscopy studies showed that the Si-C and Si-N are the main bonds in the deposited films. Concerning the C-N bonds, the results are less obvious: they are either negligible or not present at all. The films were found to be predominately amorphous with a number of crystallites within the unstructured matrix. The crystals appearance, their dimensions and crystal form did not depend on substrate temperature. We hypothesized that crystallization could happen in the gas phase during deposition or nanocrystals were formed by the strain induced after a certain thickness of the amorphous film. The crystals were assigned to the structure closed to (alpha) -Si3N4 phase. According to FTIR and XPS data it is clear that the chemical bonding and the atomic local order in the amorphous matrix are much more complicated than those of Si3N4-SiC mixtures. We concluded that tetrahedral configurations of silicon carbide and silicon nitride units with mixed C/N environment are hypothetically formed. The films are highly resistant to thermal degradation. It was also demonstrated that this new material has a band gap that was variable from 2.0 eV to 4.7 eV.
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Small copper particles within zeolite (mordenite) matrix produced by copper ion reduction were studied. Variation of SiO2/Al2O3 molar ratio of mordenite does not change crystal structure, but results in different ionic properties. A change of SiO2/Al2O3 ratio leads to transformation of the plasmon resonance from a classical peak to a shoulder in the same wavelength range. These features were simulated by the Mie theory, and calculations outlined additional absorption bands those consistent with the experiment.
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This paper reports the structural properties of lead zirconate titanate system formed in pulsed laser ablation deposition method. X-ray diffraction and scanning electron microscope was used for surface and the crystalline structure observation. The target material is prepared in conventional solid state reaction method using oxide powder. Formed lead zirconate titanate film has amorphous structure in as-deposited condition. Post-annealing treatment between 600 degree(s)C and 900 degree(s)C was carried out after deposition. Perovskite structure was formed on the Pt/Ti/SiO2/Si substrate after annealing treatment in all cases. The formed film has flat surface and homogeneous structure observed by scanning electron microscope.
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