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Nonlinear phenomena, characterized by behaviors that cannot be explained by linear systems and has significant challenges in understanding and modeling. To address this, the mathematical description of such phenomena relies on differential equations. In this study, we investigate the cubic-quintic-septimal nonlinear (7th order nonlinear media) Schrödinger wave equation, which governs the evolution of light beams in a weak non-local medium. The novelty of our study lies in the application of the improved generalized Riccati equation mapping method to obtain exact solutions for the governed equation. This scheme offers a systematic and reliable approach to exploring nonlinear phenomena, contributing to the advancement of nonlinear science and its practical applications. By applying the proposed scheme, a range of exact solutions encompassing trigonometric, rational, exponential, and hyperbolic functions are derived which offer insights into the dynamics of the light beams. Additionally, 2D and 3D graphical illustration are presented to provide a comprehensive demonstration of their dynamical behavior. Furthermore, it is important to highlight the significance of studying the cubic-quintic-septimal nonlinear Schrödinger wave equation which has application in various domains such as quantum mechanics, optics, and nonlinear wave propagation. Understanding of its solutions facilitates the design and optimization of systems involving weak non-local media. [ABSTRACT FROM AUTHOR]

This work focuses on the study of the paraxial wave model with a space–time fractional form. This model has more importance for describing light propagation in nonlinear optical fibers and telecommunication lines. The main aim of this work is to observe the effect of the fractional parameters and compare the truncated M -fraction with the beta-fraction, conformable fraction form, and classical form of the PW model. For this observation, we applied the Simplest equation technique to acquire analytical solutions to the space–time (spatiotemporal) M -fractional paraxial wave model. We are able to acquire several new optical soliton solutions, including periodic waves, kink-type waves, rogue-type waves, and several novel periodic waves, by providing the appropriate fractional parametric values. These solutions have significance for shedding light on a number of physical phenomena in the realms of optical fiber and communication sciences. The diverse values of fractional parameters and the three-dimensional and contour plot graphs of certain chosen solutions are depicted, which are the most accurate physical characterizations of the outcomes. We also sketch the comparative graph of diverse fractional forms and the classical form of the paraxial wave equation in two-dimensional plots. Consequently, our findings represent an important breakthrough in this complex area and help further develop our comprehension of the behavior of solitons. [ABSTRACT FROM AUTHOR]

In the present study, based on the multivariate nature of images from lung cancer, we extracted autoencoder, reconstruction independent component analysis (RICA) and sparse filters features along with traditional texture and morphological features. The machine learning techniques such as Support Vector Machine (SVM) with Gaussian, radial base function (RBF) and polynomial kernels, decision tree and Naïve Bayes were used classification purpose. The Jackknife 10-fold cross validation (CV) was used for training/testing data formulation and performance was evaluated in terms of sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), total accuracy (TA), false positive rate (FPR) and area under the receiving operating curve (AUC) to distinguish the small cell lung cancer (SCLC) from non-small cell lung cancer (NSCLC) images. The highest detection performance was obtained by extracting RICA and Sparse filters with 100% of sensitivity, specificity, PPV, NPV and TA using SVM with RBF, polynomial kernels and Naïve Bayes followed by Sparse filter with decision tree with TA (99.78%). The highest AUC of 1.00 was obtained by extracting RICA and Sparse filters using decision tree, SVM Gaussian, RBF and polynomial and Naïve Bayes. The results showed the good potential of these methods for lung cancer detection (LCD). [ABSTRACT FROM AUTHOR]

The generalized modified Equal–Width (GMEW) equation is often used to show how a one-dimensional wave moves through a medium that is not linear and has dispersion processes. In this article, we’ll use two very precise, cutting-edge analytical and numerical methods to find the exact traveling wave solutions for the model we’re looking at. These discoveries are really new, and they could immediately change how people train in engineering and physics. Now that a numerical approach has been described, we can roughly evaluate the replies’ accuracy. Analytical and quantitative data were shown using contour plots and two- and three-dimensional graphs. Our method of symbolic computing shows that it has the potential to be a powerful mathematical tool. It can be used to solve a wide range of nonlinear wave problems. Our findings are the outcome of our topic investigation. [ABSTRACT FROM AUTHOR]

This work considers the propagation of high-frequency waves in highly scattering media where physical absorption of a nonlinear nature occurs. Using the classical tools of the Wigner transform and multiscale analysis, we derive semilinear radiative transport models for the phase-space intensity and the diffusive limits of such transport models. As an application, we consider an inverse problem for the semilinear transport equation, where we reconstruct the absorption coefficients of the equation from a functional of its solution. We obtain a uniqueness result on the inverse problem. [ABSTRACT FROM AUTHOR]

Recently, a so-called direct method has been developed for solving 2D Maxwell’s equations in Kerr-type nonlinear media. This method is free of iteration error and more efficient than classical iterative method. We investigate this method from a theoretical point of view by proving the stability of 3D Maxwell’s equations. Numerical results have been achieved to verify the second-order convergence rate in both time and space. [ABSTRACT FROM AUTHOR]

Background. The article considers the problem of propagation of electromagnetic waves in a dielectric layer filled with a medium whose permittivity is characterized by the integral form of the Kerr law. The main task in describing the process of wave propagation in a waveguide structure is to obtain a dispersion equation for propagation constants and study its solvability. Materials and methods. Maxwell’s equations are solved in the frequency domain. The system contains the dependence on the square of the modulus of the electric field strength. Results and conclusions. A system of dispersion equations is obtained, which in fact is a system of dispersion equations for TM waves in the structure. The results of calculations of propagation constants depending on the parameters of the problem are presented.

The modified Equal-Width (MEW) equation is a fundamental model in the realm of partial differential equations that is used to simulate one-dimensional wave propagation in nonlinear media, incorporating dispersion processes. In this study, we have employed two contemporary analytical and numerical methods to obtain exact traveling wave solutions for this model. The derived solutions have been evaluated using a numerical technique, demonstrating excellent accuracy. Various graphical representations, including a contour plot, a two-dimensional graph, and a three-dimensional graph, have been utilized to illustrate and analyze the results. Our study offers significant contributions to the field by providing new insights into the dynamics of solitary wave solutions of the MEW model. Furthermore, our method proves to be a valuable and effective mathematical tool that can be utilized to solve various nonlinear wave problems, making it highly applicable in a range of physical and mathematical studies. By showcasing the properties of the investigated model and the primary advantages of the employed techniques, our study highlights the potential for further developments and advancements in this field.

The resonance conditions of two-way collinear mixing are derived when a longitudinal wave and a transverse wave are propagating in the opposite directions based on cubic nonlinearity. The analytical solutions for mixing waves are obtained. An interesting result is that the resonant longitudinal wave and the resonant transverse wave can be generated, respectively, when considering different resonance conditions. This is different from the case with quadratic nonlinearity that only resonant transverse wave can be generated. For the convenience of applications, the wave mixing of a time-harmonic longitudinal pulse and a time-harmonic transverse pulse is also investigated. A clear mixing process is presented by discussing the parameters introduced in the derivation. Numerical calculation is conducted on material Al, the hexagonal waveforms of the resonant transverse waves are depicted when considering different cases. The results could provide new opportunities for mixing wave applications in nondestructive evaluation. [ABSTRACT FROM AUTHOR]

We analyze application of a so-called approximating-functions method, a special case of a known finite-element method with polynomials of Lagrange type of the third order as interpolating functions, to solving electrodynamics problems for planar waveguides in the spatial and time domains with Volterra integral equations. Our main goal is expanding the field of applicability of the approximating-functions method towards three-dimensional problems in the time domain. This should enable solving a much wider range of problems, including those involving material media with non-stationary and nonlinear properties. We also examine whether our approach meets the general convergence criteria imposed by the finite-element method. [ABSTRACT FROM AUTHOR]

In this paper, a numerical examination of propagating nonlinear dissipative dust-acoustic breathers and rogue waves (RWs) in electron depleted dusty plasmas having two superthermal ions of different temperature has been made. An important ingredient in this study is the inclusion of the dissipative effect due to the viscosity of the dust grains in the evolution wave equation. Accordingly, a damped/modified nonlinear Schrödinger equation (DNLSE), i.e. the standard nonlinear Schrödinger equation (NLSE) in addition to the damping term, is obtained using a reductive perturbation (the derivative expansion) method. Without taking into account the effect of dust viscosity, the standard NLSE is also examined, and the effect of relevant physical parameters on the breathers and rogue waves is examined. Moreover, the impact of dust kinetic viscosity on both breather structures and RWs is investigated by solving DNLSE numerically with the Dirichlet boundary conditions. This model may be useful to understand the excitation of dust-acoustic waves in the Earth's magnetotail. [ABSTRACT FROM AUTHOR]

In this article, a finite-element time-domain method is presented for the solution of the second-order vector wave equation (VWE) subject to electrically complex materials, including general combinations of linear dispersion, instantaneous nonlinearity, and dispersive nonlinearity. The presented method is novel in that it offers greater geometric flexibility than existing finite-difference methods, incorporates both instantaneous and dispersive nonlinearity, scales to arbitrary dispersive and nonlinear orders, and is simpler, faster, and requires less computational complexity than existing mixed formulations due to the use of edge elements only. [ABSTRACT FROM AUTHOR]

In this paper, we study the propagation and evolution of higher-order mixed-pattern solitons in nonlinear media with a strong nonlocality. The propagation analytic formula of higher-order mixed-pattern solitons is derived and discussed in detail. Taking the fourth-order mixed-pattern solitons as an example and based on numerical calculations, we present the variations of second-order moment beam width, the light intensity, and the wavefront curvature. We show that the propagation evolution exhibits unique characteristics depending on different relative factors of higher-order mixed-pattern solitons. The influence of the beam order on the propagation evolution is also discussed. [ABSTRACT FROM AUTHOR]

In this paper, we develop a totally new direct finite difference solver for solving the Maxwell's equations in Kerr-type nonlinear media. The direct method is free of iteration error and more efficient than the classic iteration method. We also prove the continuous stability for the Kerr model and the discrete stability for the proposed scheme. Extensive numerical results are presented to validate our analysis. [ABSTRACT FROM AUTHOR]

A novel implementation of a perfectly matched layer (PML) is presented for the truncation of finite-element time-domain (FETD) meshes containing electrically complex materials, exhibiting any combination of linear dispersion, instantaneous nonlinearity, and dispersive nonlinearity. Based on the complex coordinate stretching formulation of the PML, the presented technique yields an artificial absorbing layer whose matching condition is independent of material parameters. Moreover, by virtue of only modifying spatial derivatives, the incorporation of the PML into existing solvers for complex media is simple and straightforward. The resulting material-independent PML is incorporated into a nonlinear dispersive method for the vector wave equation, which leverages the $z$ transform and Newton-Raphson techniques to yield an implementation free from recursive convolutions, auxiliary differential equations, and linearizations. This permits the unprecedented truncation and attenuation of nonlinear phenomena, such as spatial and temporal solitons, within the FETD method. [ABSTRACT FROM AUTHOR]

In this paper, a mixed finite-element time-domain (FETD) method is presented for the simulation of electrically complex materials, including general combinations of linear dispersion, instantaneous nonlinearity, and dispersive nonlinearity. Using both edge and face elements, the presented method offers greater geometric flexibility than existing finite-difference time-domain (FDTD) implementations, and in contrast to existing nonlinear FETD methods, also incorporates both linear and nonlinear material dispersions. Dielectric nonlinearity is incorporated into the Crank–Nicolson mixed FETD formulation via a straightforward Newton–Raphson approach, for which the associated Jacobian is derived. Moreover, the dispersion is modeled via the Möbius $z$ transform method, yielding a simpler more general algorithm. The method’s accuracy and convergence are verified, and its capability demonstrated via the simulation of several nonlinear phenomena, including temporal and spatial solitons in two spatial dimensions. [ABSTRACT FROM AUTHOR]

Statements and analysis are presented of nonselfadjoint eigenvalue problems for elliptic equations and systems, including singular Sturm-Liouville problems on the line, that arise in mathematical models of the wave propagation in open metal-dielectric waveguides. Existence of real and complex spectra are proved and their distribution is investigated for canonical structures possessing circular symmetry of boundary contours. [ABSTRACT FROM AUTHOR]

The modified Equal-Width (MEW) equation is a fundamental model in the realm of partial differential equations that is used to simulate one-dimensional wave propagation in nonlinear media, incorporating dispersion processes. In this study, we have employed two contemporary analytical and numerical methods to obtain exact traveling wave solutions for this model. The derived solutions have been evaluated using a numerical technique, demonstrating excellent accuracy. Various graphical representations, including a contour plot, a two-dimensional graph, and a three-dimensional graph, have been utilized to illustrate and analyze the results. Our study offers significant contributions to the field by providing new insights into the dynamics of solitary wave solutions of the MEW model. Furthermore, our method proves to be a valuable and effective mathematical tool that can be utilized to solve various nonlinear wave problems, making it highly applicable in a range of physical and mathematical studies. By showcasing the properties of the investigated model and the primary advantages of the employed techniques, our study highlights the potential for further developments and advancements in this field. • Nonlinear dynamics' investigation of modified Equal-Width. • Analytical and numerical novel constructed results. • Investigating the obtained results' accuracy. • Explaining the obtained solutions through some distinct types of sketches. [ABSTRACT FROM AUTHOR]

This paper is an attempt to compare the nonlinear chiroptical and non-reciprocity effects of bi-isotropic media. The nonlinearity used is of a Kerr type. Following the approach of Mezache--Benabdelaziz, recently new nonlinear effects are characterized in a bi-anisotropic medium, which is due to the magnetization vector under the influence of a strong electric field. We then use these results to present the solution of nonlinear Schrödinger equation in the general case of bi-isotropic (chiral and non-reciprocal). Numerical simulations were carried out, in order to confirm the effect of the nonlinear chiroptical and non-reciprocity on the propagation analysis. [ABSTRACT FROM AUTHOR]

We propose to exploit the quantum properties of nonlinear media to estimate the parameters of massless wormholes. The spacetime curvature produces a change in length with respect to Minkowski spacetime that can be estimated in principle with an interferometer. We use quantum metrology techniques to show that the sensitivity is improved with nonlinear media and propose a nonlinear Mach⁻Zehnder interferometer to estimate the parameters of massless wormholes that scales beyond the Heisenberg limit.

Modeling of a light pulse propagating in optical fiber where the core is bi-isotropic non-reciprocal achiral media (i.e., Tellegen media) with Kerr effect is studied. The two constitutive equations approach for nonlinear bi-isotropic media are proposed to highlight nonlinear effect, which is due to the magnetization vector under the influence of a strong electric field. According to this approach, nonlinear parameter of magnetization vector is illustrated; it is the important factors to estimate bi-isotropic optical fiber dispersion and nonlinearity. Split-step Fourier method is used to simulate and solve the nonlinear Schrödinger equation. [ABSTRACT FROM AUTHOR]

Bilayers of VDF-TrFE ferroelectric copolymer thin films have been characterised in terms of polarisation behaviour and dielectric nonlinearities. The effective properties of the ferroelectric bilayers have been investigated and compared with those of the individual layers in the stack. It has been demonstrated that the effective permittivity of the bilayer is not fully described by a simple series model. The remanent polarisation Pr in the bilayer shows essentially a linear decrease with temperature and reaches zero at around 120 ° C, i.e. above the Curie temperatures of the two copolymers involved. The two observations are attributed to electric bias fields in the bilayer which cause a coupling between the two layers and lead to a temperature dependence of the polarisation which is phenomenologically similar to observations in superlattices. [ABSTRACT FROM PUBLISHER]

Full-wave analysis of the time-harmonic field originated in waveguide devices containing nonlinear materials, possibly anisotropic, is addressed in this article. The approach combines finite elements and harmonic balance handling the nonlinearity via either Picard or relaxed iterations. To speed-up computation, domain decomposition is exploited to restrict the iteration to a small subdomain. [ABSTRACT FROM AUTHOR]

This paper presents an efficient method to determine the actuating time of DC fed electromagnets. In order to acheive it, the motion equation of the moving armature was solved using a numerical integration method. This method is illustrated by applying it to an E-E type electromagnet for which the velocity and the actuation time of the moving armature is determined, the results are obtained by theoretical methods. The attraction force applied to the moving armature was calculated using the finit element analysis software FEMM 2D for stationary conditions of the magnetic field in nonlinear media. The initial velocity of the moving armature was obtained considering the transient conditions of the feeding current, thus illustrating a comprehensive model for the determination of the dynamic behaviour of the studied electromagnet. [ABSTRACT FROM AUTHOR]

We have observed the piezoelectric and elastooptic effects for the 2-cyclooctylamino-5-nitropyridine complex, chromophore doped by an inter-molecular acceptor -- fullerene C70. The discovered features may be used for optically operated piezoelectric triggers, modulators and deflectors. The observed effects are caused by the effective interaction of external light with the polarizable chromophore. As a pumping laser beam we have used both a nanosecond fundamental 1064 nm laser wavelength as well as its second harmonic generation at 532 nm. A principal role in the observed effects play photoinduced anharmonic phonons, effectively contributing to the output effect. [ABSTRACT FROM AUTHOR]

Thin VDF-TrFE copolymer films of molar composition 70/30 and thickness from 25 nm to 175 nm have been prepared by spin coating on a glass substrate covered with an aluminum electrode. The linear, second and third order permittivities ϵ1, ϵ2 and ϵ3 of poled and unpoled samples have been studied versus temperature in heating and cooling cycles up to 120 °C, i.e., above the Curie temperature. The polarization and its temperature dependence are derived from ϵ1 and ϵ2 . This allows a non-destructive readout of the polarization state. It is found that above the Curie temperature and after cooling to room temperature a non-switchable polarization remains. This nonswitchable polarization points from the bottom to the top electrode and is not influenced by the initial polarization direction. [ABSTRACT FROM PUBLISHER]

This paper studies the Davey–Stewartson equation. The traveling wave solution of this equation is obtained for the case of power-law nonlinearity. Subsequently, this equation is solved by the exponential function method. The mapping method is then used to retrieve more solutions to the equation. Finally, the equation is studied with the aid of the variational iteration method. The numerical simulations are also given to complete the analysis. [ABSTRACT FROM PUBLISHER]

An innovative method for fast analysis of electromagnetic problems comprising nonlinear dielectrics is proposed. The method is based on the combination of finite elements and domain decomposition methods. This latter technique allows for the separation of the problem in multiple subproblems which can be solved separately. By appropriately defining one of such subdomains as containing all the nonlinear dielectrics it is possible to restrict the application of an iterative algorithm for the numerical solution of nonlinear equations only to this latter, smaller, domain. Numerical results showing the accuracy and efficiency of this technique are presented in few 2D cases. [ABSTRACT FROM AUTHOR]

We show that spin-squeezing implies entanglement for the quantum tripartite state, where the subsystem of the bipartite state is identical. We study the relation between spin-squeezing parameters and entanglement through the quantum entropy of a system, starting initially in a pure state when the cavity is binomial. We show that spin-squeezing can be a convenient tool to give some insight into the subsystems entanglement dynamics when the bipartite subsystem interacts simultaneously with the cavity field subsystem, especially when the interaction occurs off-resonantly without and with a nonlinear medium contained in the cavity field subsystem. We illustrate that, in the case of large off-resonance interaction, spin-squeezing clarifies the properties of entanglement almost with full success. However, it is not a general rule when the cavity is assumed to be filled with a nonlinear medium. In this case, we illustrate that the insight into entanglement dynamics becomes more clear in the case of a weak nonlinear medium than in strong nonlinear medium. In parallel, the role of the phase-space distribution in quantifying entanglement is also studied. The numerical results of Husimi Q-function show that the integer strength of the nonlinear medium produces Schrödinger cat states, which is necessary for quantum entanglement. [ABSTRACT FROM AUTHOR]

Application of the current sheet integral equation for an efficient analysis of the electromagnetic field in the presence of thin shields is limited to the case of nonferromagnetic and homogeneous media. An extension of this method to thin shields in the vicinity of ferromagnetic bodies is proposed in this paper for time-harmonic fields. The fixed-point polarization technique is used, where the nonlinear material is replaced by a free space and a distribution of fictitious polarization whose magnitude is corrected iteratively in terms of the magnetic induction. A Fourier decomposition of the polarization is employed and the integral equation is solved for each harmonic. The procedure has a guaranteed convergence and is more and more rapid as the number of harmonics retained decreases. In the beginning only the fundamental harmonic is considered and, afterward, higher order harmonics are added to increase the computation accuracy. [ABSTRACT FROM AUTHOR]

Abstract: The spatial dynamics of pulses in Kerr media with parabolic index profile are examined. It is found that when diffraction and graded-index have opposite signs propagating pulses exhibit an oscillatory pattern, similar to a breathing behavior. Furthermore, if the pulse and the index profile are not aligned the pulse oscillates around the index origin with frequency that depends on the values of the diffraction and index of refraction. These oscillations are not observed when diffraction and graded-index share the same sign. [Copyright &y& Elsevier]

We model the propagation of femtosecond pulses through optical fibres by a nonlinear Schrödinger (NLS) equation involving a perturbing term arising due to third-order dispersion in the medium. The perturbative effect of this higher-order dispersion causes the usual NLS soliton to emit a radiation field. As a result, the given initial pulse propagating through the fibre exhibits nonsolitonic behaviour. We make use of a variational method to demonstrate how an initial pulse by the interaction with the emitted radiation can evolve into a soliton. We also demonstrate that the effect of interaction between the initial pulse and radiation field can be accounted for by including, in the evolution equation, terms associated with self-steepening and stimulated Raman scattering that characterize the optical medium. [ABSTRACT FROM AUTHOR]

We show that, under certain conditions, the micromaser can act as an effective source of highly correlated atoms. It is possible to create an extended robust entanglement between two successive, initially unentangled atoms passing through a cavity filled with a nonlinear medium taking into consideration a slight level shift. Information is transferred from the cavity to the atoms in order to build up entanglement. The scheme has an advantage over conventional creation of entanglement if the two atoms (qubits) are so far apart that a direct interaction is difficult to achieve. The interaction of the atoms with the micromaser occurs under the influence of a two-quantum transition process. Interesting phenomena are observed, and an extended robust entangled state is obtained for different values of the system parameters. Illustrative variational calculations are performed to demonstrate the effect within an analytically tractable two-qubit model. [ABSTRACT FROM AUTHOR]

TM electromagnetic waves propagating through a nonlinear homogeneous isotropic unmagnetized dielectric layer located between two homogeneous isotropic half-spaces are studied. The nonlinearity in the layer obeys the Kerr law. The problem is reduced to a system of nonlinear ordinary differential equations. A dispersion relation for the propagation constants is derived. The results are compared with those in the case of a linear layer. [ABSTRACT FROM AUTHOR]

Conventional video consists of a single sequence of video frames. During a client's playback period, frames are viewed sequentially from some specified starting point. The fixed frame ordering of conventional video enables efficient scheduled broadcast delivery, as well as efficient near on-demand delivery to large numbers of concurrent clients through use of periodic broadcast protocols in which the video file is segmented and transmitted on multiple channels. This paper considers the problem of devising scalable protocols for near on-demand delivery of “nonlinear” media files whose content may have a tree or graph, rather than linear, structure. Such media allows personalization of the media playback according to individual client preferences. We formulate a mathematical model for determination of the optimal periodic broadcast protocol for nonlinear media with piecewise-linear structures. Our objective function allows differing weights to be placed on the startup delays required for differing paths through the media. Studying a number of simple nonlinear structures we provide insight into the characteristics of the optimal solution. For cases in which the cost of solving the optimization model is prohibitive, we propose and evaluate an efficient approximation algorithm. [ABSTRACT FROM PUBLISHER]

We compare three different approaches for low cost all-optical swapping of spectral amplitude code labels for packet-switched networks. The first uses cross-absorption modulation in an electroabsorption modulator within a semiconductor fiber ring laser (SFRL), the second uses cross-gain modulation (XGM) in a semiconductor optical amplifier (SOA) within an SFRL, and the third makes use of XGM in an SOA as well as injection locking in a Fabry-Perot laser diode for wavelength conversion. We examine both the static and dynamic responses of each for swapping a multiwavelength input label to a multiwavelength output label. The benefits and limitations of each approach as well as future improvements are discussed. [ABSTRACT FROM PUBLISHER]

A conventional video file contains a single temporally-ordered sequence of video frames. Clients requesting on-demand streaming of such a file receive (all or intervals of) the same content. For popular files that receive many requests during a file playback time, scalable streaming protocols based on multicast or broadcast have been devised. Such protocols require server and network bandwidth that grow much slower than linearly with the file request rate. This paper considers "nonlinear" video content in which there are parallel sequences of frames. Clients dynamically select which branch of the video they wish to follow, sufficiently ahead of each branch point so as to allow the video to be delivered without jitter. An example might be "choose-your-own-ending" movies. With traditional scalable delivery architectures such as movie theaters or TV broadcasting, such personalization of the delivered video content is very difficult or impossible. It becomes feasible, in principle at least, when the video is streamed to individual clients over a network. For on-demand streaming of nonlinear media, this paper analyzes the minimal server bandwidth requirements, and proposes and evaluates practical scalable delivery protocols. [ABSTRACT FROM AUTHOR]

In this paper, the numerical studies on optical-bistability phenomena in third-, fifth-, and seventh-order nonlinear periodic media are presented. By cross-phase modulation with strong Gaussian pump, the continuous-wave probe transmission that operates in bistability regime can be permanently switched from low to high and vice versa using the property of the unstable state. While there is only one hysteresis in the third-order nonlinear periodic media, double hysteresis are observed in the nonlinear-transmission characteristics of pi phase-shifted periodic media with third-fifth and third-fifth-seventh-order nonlinearities. In the context of double hysteresis, unique-bistability regime is defined where the high state can be reached as input comes from low to high with fast enough rise time such that the output rises above the unstable state during its transient. Finally, all-optical transistor operation is shown as a prominent application of optical bistability based on the unstable-state principle [ABSTRACT FROM PUBLISHER]

We study how to employ space-time dynamics in nonlinear media to achieve distributed manipulation of objects — positioning, orienting and transporting objects by wave-fronts and patterns in excitable medium. We present the results of computational experiments of a massive parallel actuator controlled by a cellular-automaton model of an excitable medium. The model incorporates closed-loop actuation where sites of the medium can be excited not only by their closest neighbors but also by the edges of the manipulated object. We analyze motion of basic planar shapes (either initially aligned along axes or randomly oriented) induced by an actuator controlled by excitable lattice with various excitation rules. We demonstrate that space-time excitation dynamics in discrete nonlinear media bears a huge potential in terms of sensible nontrivial manipulation of planar shapes. [ABSTRACT FROM AUTHOR]

Delay bandwidth products (DBPs) and physical pulselengths obtainable in media exhibiting electromagnetically induced transparency (EIT) are analyzed. The study is performed in stationary media as well as for dynamic storing of light pulses in such media. In the latter case, the dispersion inherent in storage and readout of the pulses is analyzed. It is shown that absorption and the group velocity dispersion (GVD) are limiting factors. Analytical expressions for the minimum compressed pulselength and DBP are derived, and these expressions show good agreement with simulations of pulse propagation in EIT media. [ABSTRACT FROM PUBLISHER]

A new three-dimensional (3-D) full-vectorial finite-difference (FD)-based beam-propagation method (BPM) is introduced for the analysis of magnetooptic and nonlinear materials. The refractive-index growth in the nonlinear material is allowed to saturate at high optical power densities (cubic-quintic media). The new formalism is capable of handling any combination of linear, nonlinear, and magnetooptic media, and combines, for the first time, the alternating-direction implicit technique (to improve computational performance) with the leapfrog longitudinal scheme (to simplify the solution of the coupled equations for transverse field components). The result is a numerical method that is both computationally efficient and numerically robust. The proposed BPM formalism is applied to investigate a (nonreciprocal) magnetooptic rib waveguide, as well as the new striking phenomena of light condensates propagation in cubic-quintic (saturable) media, the dynamics of which resemble those of liquid droplets. [ABSTRACT FROM PUBLISHER]

We investigate the coupling efficiency of parametric downconversion light (PDC) into single and multimode optical fibers as a function of the pump beam diameter, crystal length, and walk-off. We outline two different theoretical models for the preparation and collection of either single-mode or multi-mode PDC light (defined by, for instance, multimode fibers or apertures). Moreover, we define the mode-matching collection efficiency, important for realizing a single-photon source based on PDC output into a well-defined single mode. We also define a multimode collection efficiency that is useful for single-photon detector calibration applications. [ABSTRACT FROM AUTHOR]

We propose all-optical logic gates by using a multibranch waveguide structure with localized optical nonlinearity. By simply setting nonlinear media in the selected output guides and properly launching the input power, the numerical results show that the proposed all-optical waveguide structure could really function as AND and OR logic gates. [ABSTRACT FROM PUBLISHER]