Richard Kowarschik

TL;DR: In this article, the authors investigated the influence of optical activity on incoherent interaction of soliton-like light beams in cubic photorefractive crystal and showed that under influence of the optical activity, the distance between the points of beam fusion increases and the first fusion point is shifted from input face of the crystal.

Abstract: The dynamics of the formation of 3D light self-trapping waveguides in a volume photopolymeric medium, namely polymethyl methacrylate (PMMA) with photosensitive phenanthrenequinone (PQ)-molecules, has been studied theoretically and experimentally. The different contributions of two competing nonlinear mechanisms with the formation of the photoproduct and with the heating of the medium due to absorption have been analyzed. To describe the propagation dynamics of laser beams in the photopolymeric material, a theoretical model has been proposed including heat conduction and diffusion equations in conditions of spatially inhomogeneous light-induced heating of the medium together with the kinetic equations for the photoreactions which proceed within the photopolymeric material. The principal patterns for the spatial and temporal dynamics of the formation of 3D selftrapping waveguides in thick absorbing layers of PQ-PMMA with concurrent nonlinear mechanisms have been established theoretically and verified experimentally.

TL;DR: In this article, the authors compare different ways of realizing an optical novelty filter with photorefractive barium titanate crystals and present experiments on the basis of beam fanning, two-wave mixing and self-pumped phase conjugate geometries.

TL;DR: In this paper, the fidelity of a self-pumped phase conjugating mirror (SPPCM) in the so-called cat configuration is studied with an interferometric method for a cobalt-doped barium titanate crystal (BaTiO3:Co) under pulse illumination (8 ns, 532 nm).

TL;DR: In this article, a verfahren zur Erzeugung von wiederholbaren, koharenter Mustern gelost, bei dem das von wenigstens einer Lichtquelle stammende Licht durch weniusens ein weiteres Element wieserholt dieselbe Phasenanderung der Wellenfront erfahrend kann.