ABSTRACT
Xavier Arys, Alain M. Jonas, Andre´ Laschewsky, and Roger Legras Universite´ Catholique de Louvain, Louvain-La-Neuve, Belgium
I. INTRODUCTION
In recent years, much progress has been achieved in the preparation and characterization of organic and hybrid organic-inorganic ultrathin multilayers. The growing interest for these systems, both from the fundamental and from the applied side, is partly due to the unusual physical properties of nanostructured materials, and to the potential applications resulting from these properties, in particular in the field of integrated molecular optics and electronics. Size quantization, for instance, occurs when electron-hole pairs are confined in domains whose dimensions are comparable to the wavelength of the de Broglie electron, and the mean free path of excitons [1]. This in turn enables the control of the emission color of light-emitting diodes (LEDs) [2]. Another reason for the current growing interest in organic multilayer films is the similarity among the methods for obtaining such molecular assemblies and the principles governing the self-organization of organic molecules in natural systems [3,4]. Being able to control the spatial arrangement of biological molecules on a nanometer scale opens the way to numerous applications, among which molecular recognition [5] and multistep catalysis [6] can be cited. At the frontier between biology and physics, molecular bioelectronics is also gaining in interest [7]. An example of development in this field is the fabrication of systems that mimic photosynthesis, the goal being to design artificial systems for the efficient conversion of solar energy into chemical or electrical energy [8-10].
