Soliton generation and control in engineered materials

Optical solitons provide unique opportunities for the control of light‐bylight. Today, the field of soliton formation in natural materials is mature, as the main properties of the possible soliton states are well understood. In particular, optical solitons have been observed experimentally in a variety of materials and physical settings, including media with cubic, quadratic, photorefractive, saturable, nonlocal and thermal nonlinearities. New opportunities for soliton generation, stability and control may become accessible in complex engineered, artificial materials, whose properties can be modified at will by, e.g., modulations of the material parameters or the application gain and absorption landscapes. In this way one may construct different types of linear and nonlinear optical lattices by transverse shallow modulations of the linear refractive index and the nonlinearity coefficient or complex amplifying structures in dissipative nonlinear media. The exploration of the existence, stability and dynamical properties of conservative and dissipative solitons in settings with spatially inhomogeneous linear refractive index, nonlinearity, gain or absorption, is the subject of this PhD Thesis. We address stable conservative fundamental and multipole solitons in complex engineered materials with an inhomogeneous linear refractive index and nonlinearity. We show that stable two‐dimensional solitons may exist in nonlinear lattices with transversally alternating domains with cubic and saturable nonlinearities. We consider multicomponent solitons in engineered materials, where one field component feels the modulation of the refractive index or nonlinearity while the other component propagates as in a uniform nonlinear medium. We study whether the cross‐phase‐modulation between two components allows the stabilization of the whole soliton state. Media with defocusing nonlinearity growing rapidly from the center to the periphery is another example of a complex engineered material. We study such systems and, in contrast to the common belief, we have found that stable bright solitons do exist when defocusing nonlinearity grows towards the periphery rapidly enough. We consider different nonlinearity landscapes and analyze the types of soliton solution available in each case. Nonlinear materials with complex spatial distributions of gain and losses also provide important opportunities for the generation of stable one‐ and multidimensional fundamental, multipole, and vortex solitons. We study onedimensional solitons in focusing and defocusing nonlinear dissipative materials with single‐ and double‐well absorption landscapes. In two‐dimensional geometries, stable vortex solitons and complexes of vortices could be observed. We not only address stationary vortex structures, but also steadily rotating vortex solitons with azimuthally modulated intensity distributions in radially symmetric gain landscapes. Finally, we study the possibility of forming stable topological light bullets in focusing nonlinear media with inhomogeneous gain landscapes and uniform twophoton absorption

Stabilization of two-dimensional solitons in cubic-saturable nonlinear lattices

We consider soliton dynamics and stability in a nonlinear lattice formed by alternating domains with focusing cubic and saturable nonlinearities. We find that in such lattices solitons centered on cubic domains may be stabilized even in two-dimensional geometries, in spite of their intrinsic catastrophic instability in the absence of the lattice. Solitons centered on saturable domains are always unstable.Comment: 16 pages, 5 figures, to appear in Physical Review

Estimation and prediction for nonlinear time series

In verschillende situaties verschijnt informatie als een rij van opeenvolgende metingen, een zogenaamde tijdreeks. De analyse van zulke tijdreeksen is gericht op het modelleren de onderliggende correlaties. Op deze manier probeert men inzicht te verkrijgen in de achterliggende mechanismes. Een belangrijke toepassing is het voorspellen van toekomstige waardes. Traditioneel werden lineaire modellen gebruikt, zoals AR en ARMA, waarin een volgende observatie een lineaire combinatie van voorgaande observaties is, samen met een onafhankelijke verstoring. Er zijn desalniettemin voorbeelden van tijdreeksen, zoals tijdreeksen gerelateerd aan chaotische dynamische systemen, waarvoor lineaire modellen zijn geschikt zijn wegens de sterke invloed van niet-lineariteiten. Dit werpt een aantal vragen op: hoe zulke tijdreeksen te herkennen en wat voor niet-lineaire methoden te gebruiken voor modellering en voorspelling. Dit proefschrift is een poging enkele nieuwe bijdragen te leveren aan de theorie van niet-lineaire tijdreeksen. ... Zie: Samenvatting

LEGAL EDUCATION AS A METHOD FOR MITIGATING DEVIANT BEHAVIOR OF MINORS

Abstract. This article studies legal education as a method for mitigating deviantbehavior of minors. It analyzes importance of legal culture of teens that can be fostered by forms and methods of educational environment, improves activity of the young, regulated individual behavior based on moral motivation of the personality. Need and expediency of sense of justice which acquaints minors with knowledge of the state and the right, legality, the rights and personal freedoms, development at teenagers of steady orientation to law-abiding behavior is defined.Keywords: legal education, educational environment, deviant behavior, moralmotivation

Formation of organizational culture by meaning of the mechanism of the interior of values

Культивирование ценностей в среду организации – достаточно длительный и сложный процесс. Актуальность исследований в данном направлении обусловлена тем обстоятельством, что традиционные методы формирования организационных ценностей у новичков компании уже не работают, что актуализирует поиск новых путей и механизмов интериоризации ценностей. В данной статье автором затронута проблема совершенствования организационной культуры посредством воздействия на глубинный уровень сознания работника в целях формирования определенных моделей действий, образцов поведения, социального участия, а также ожидаемого поведения со стороны как новых, так и уже работающих сотрудников.The mechanism of cultivating values in your environment rather long and complicated process. But to date, this aspect is important because the traditional methods do not work today, and employee behavior is impossible to predict. Is why in this article the author is concerned the problem of improving the organizational culture through exposure to the deep level of human consciousness. Thereby is formed a certain model of action samples, social participation, motivation to the process, as well as the expected behavior on the part of the labor potential. The urgency of research in this direction is due to the circumstances in which traditional methods of formation of organizational values beginners companies no longer work. Consequently, the search for new ways and mechanisms of internalization of values becomes more urgent

Dynamic versus Anderson wavepacket localization

We address the interplay between two fundamentally different wavepacket localization mechanisms, namely resonant dynamic localization due to collapse of quasi-energy bands in periodic media and disorder-induced Anderson localization. Specifically, we consider light propagation in periodically curved waveguide arrays on-resonance and off-resonance, and show that inclusion of disorder leads to a gradual transition from dynamic localization to Anderson localization, which eventually is found to strongly dominate. While in the absence of disorder, the degree of localization depends critically on the bending amplitude of the waveguide array, when the Anderson regime takes over the impact of resonant effects becomes negligible.Comment: 13 pages, 5 figures, to appear in Physical Review