Björn Gütlich

Dynamic and static position control of optical feedback solitons.

We report on the experimental implementation of an external control for optical feedback solitons using incoherent spatial intensity distributions in a liquid crystal light valve (LCLV) optical single feedback system. The external control provides excellent experimental possibilities for static and dynamic control of the lateral positions of the optical feedback solitons which will be demonstrated. Particularly, the influence of different gradients onto the drift motion of spatial solitons is experimentally investigated in detail. In agreement with theoretical predictions, the drift velocity of the soliton increases according to the steepness of the gradient. Additionally, a completely incoherent addressing scheme including creation and erasure of feedback solitons is demonstrated for the LCLV setup.

Dynamic Control of Localized Structures in a Nonlinear Feedback Experiment

Spatial dissipative solitons exhibit a robust form as well as complex dynamic behaviour that make them attractive for applications in the context of all– optical information processing. In this chapter we give an overview of recent experimental and theoretical results on the features of spatial dissipative solitons in a single feedback experiment using a liquid crystal light valve (LCLV) as a model nonlinear medium. In particular, we present techniques for the control of the symmetry and spatial position of localized states in LCLV based experiments. We first discuss the interaction of dissipative solitons with spatially imposed boundary constraints in the feedback loop. This interaction leads to symmetry-breaking phenomena of feedback dissipative solitons. We also present static and dynamic techniques to experimentally control and guide dissipative solitons on modified background by using externally adapted intensity distributions.

Gradient-induced position trapping and guiding of solitary structures in an LCLV single feedback experiment

This article investigates a lateral position control of solitary structures required to suppress mutual interaction and spontaneous dynamics. The system used is an LCLV single feedback experiment in polarisation mode, with bistable behaviour and modulation instabilities.

Synchronization of spatiotemporal disorder

A nonlinear optical single feedback system is used to explore the effect of spatiotemporal synchronization. The synchronization scheme under consideration is the unidirectional coupling of identical systems. In our experiments, we use a liquid crystal light valve (LCLV) in a single optical feedback system as saturable Kerr nonlinearity. In this system, the formation of hexagonal, i.e. periodic patterns is observed above threshold.

Drift Motion Control of Solitary Structures Using Parameter Gradients

We study the drift motion control of solitary structures with parameter gradients. The dependence of drift velocity on gradient slope and spatial dimensions of the gradient is determined and guiding of drifting solitons is demonstrated.

Positioning and Addressing of Solitary Structures in a Nonlinear Optical Single Feedback Experiment

Interactions challenge the implementation of solitary structures in context of optical information processing. We investigate control of solitary structures with white light input and demonstrate compensation of inhomogeneity, dynamic and static positioning of solitary structures.