Nonlinear Optical Patterns: Applications to SpatialSoliton Arrays, Quantum Aspects

In this article we discuss two aspects of nonlinear optical patterns. The first concernsthe possibility of a future application to information processing, based on the realization of arraysof spatial soliton pixels in broad area semiconductor microcavities. We outline the concepts, thecontrol and the perspectives. The second aspect concerns the quantum features of nonlinearoptical patterns. We discuss the concept of quantum image in the framework of parametricdown-conversion processes. Numerical simulations show the transition from a quantum image toa classical image across the threshold region of a degenerate optical parametric oscillator. Anexperiment with lithium triborate shows strikingly similar results in both the near and the far field,displaying qualitatively the classical features of quantum images.