Spatio-temporal localization in dissipative and discrete systems

与前一阶段一样，该理论项目旨在为耗散和/或离散光学系统中的非线性局部化理论提供真正的贡献，并弥合研究单元中进行的实验的差距。这项工作将分为四个工作包：a）时间耗散孤子，B）超材料中的腔孤子，c）波导阵列中的时空定位和d）实验组的理论支持。在工作包（a）中，将研究耗散光学系统中的时间孤子。我们将集中在两个系统，即第一个周期性的半导体器件，由半导体光放大器（SOA），可饱和吸收体（SA）和过滤器，其次是一个短脉冲光纤激光器系统与适当的被动锁模机制。我们以前的研究表明，前一个系统可能表现出耗散孤子解，没有真正分类和理解的日期，但可能潜在地作为超快脉冲再生器。后者系统是最重要的兴趣，产生短脉冲具有一定的属性，但也被认为是最有前途的试验台之一耗散孤子动力学。这两个主题都涉及到一个基本的问题仍然需要解决，即真正确定所有的属性，并利用有吸引力的特性耗散孤子在系统中的未来大的应用potenties.Work包（B）将解决腔孤子的研究作为一个自然的延续，我们的工作离散腔孤子的超材料。其目的是研究可剪裁的线性特性的微和纳米结构的超材料和平面腔中的各种非线性之间的相互作用。人们期望通过工程色散和衍射，将存在新的腔孤子。超材料的范围将从二维波导阵列，通过光子晶体负折射率材料。利用耗散系统固有的增益，其特征在于与环境进行稳定的能量交换，损耗，这被认为是所谓的负折射率超材料的关键问题，可以克服这里。离散系统中的时空效应和光局域化将是工作包（c）的重点。利用二维波导阵列的多功能色散关系和使用具有增益和损耗的波导阵列（耗散系统），有望获得新的效果。一般将研究保守和耗散结构中的光学子弹。这些项目符号将是离散-连续对象。一个主要目标将是研究相干耦合有源光纤中的脉冲产生。理论模型将包括紧束缚方程和更一般的晶格方法。我们的工作将通过工作包（d）完成，该工作包致力于提供我们在耗散和离散系统方面的理论专业知识，并为实验伙伴设计实验和评估结果提供先进的建模工具。在这一合作范围内，还将提供必要的高级建模能力。

As in the previous period this theoretical project aims at both providing genuine contributions to the theory of nonlinear localization in dissipative and/or discrete optical systems and bridging the gap to the experiments performed in the research unit. The work will be organized in four work packages a) temporal dissipative solitons, b) cavity solitons in metamaterials, c) spatio-temporal localization in waveguide arrays and d) theoretical support for experimental groups. In work package (a) temporal solitons in dissipative optical systems will be investigated. We shall focus on two systems, namely first a periodic semiconductor device that consists of a semiconductor optical amplifier (SOA), a saturable absorber (SA) and a filter and secondly a short-pulse fibre laser system with an appropriate passive mode-locking mechanism. Our previous studies imply that the former system may exhibit dissipative soliton solutions, not really categorized and understood to date, but may potentially serve as ultrafast pulse regenerator. The latter system is of paramount interest for the generation of short pulses with definite properties, but is also considered as one of the most promising test beds for dissipative soliton dynamics. Both subjects are related to a fundamental issue still to be addressed, namely to really identify all properties and to take advantage of the attractive peculiarities of dissipative solitons in systems with a future large application potential.Work package (b) will address the study of cavity solitons metamaterials as a natural continuation of our work on discrete cavity solitons. The aim is to investigate the interplay between tailorable linear properties of micro- and nanostructured metamaterials and various nonlinearities in planar cavities. It is expected that by engineering dispersion and diffraction new classes of cavity solitons will exist. Metamaterials looked at will range from 2D waveguide arrays, via photonic crystals to negative refractive index materials. Using the gain inherent to dissipative systems, which are characterized by a steady energy exchange with the environment, the losses, which are considered a critical issue for so-called negative index metamaterials, can potentially be overcome here.Spatio-temporal effects and light localization in discrete systems will be the focus in work package (c). Novel effects are expected from exploiting the versatile dispersion relation of two-dimensional (2D) waveguide arrays and by using waveguide arrays with gain and loss (dissipative system). Optical bullets in conservative as well as dissipative configurations will be studied in general. These bullets will be discrete-continuous objects. One major goal will be to study pulse generation in coherently coupled active fibres. Theoretical models will include tight-binding equations and the more general lattice approach.Our work will be completed by work package (d) that is devoted to providing our theoretical expertise in dissipative and discrete systems and the access to advanced modelling tools to the experimental partners in designing experiments and in evaluating their results. Within this collaboration also the necessary advanced modelling capacity will be provided.