Déformation photoinduite dans les films minces contenant des ...

Introduction 3Subsequently, we use a configuration where the interference pattern is assisted by a thirdincoherent beam. In this configuration, previous studies have shown that the efficiencyof the photodeformation process is strongly increased [5]. In our experiment, since wemeasure in real-time both the intensity pattern and the topography, we have access tothe direction of the mass transport with respect to the optical pattern. We demonstratethat in sol-gel Si-DR1 films the direction of the mass transport depends on the lightpolarization distribution. Thus, for a given intensity pattern, switching in real-time thelight polarization produces an alternating photoinduced mass transport. This clearlydemonstrates both the directionality and the reversibility of the matter migration. In aPMMA-DR1 film, the assisting-beam experiment exhibits two subsequent matter transportregimes, which result from the competition of the intensity and polarization drivenprocesses. At a short time scale the intensity dependent mechanism is dominant, whereasat longer time scale, the polarization dependent mechanism prevails.pastel-00527388, version 1 - 19 Oct 2010In Chapter 4, we demonstrate the possibility to use the photodeformation properties ofazobenzene containing materials for the patterning of hybrid metal/azo-polymer structures.We show that the photodeformation induced in the underlying photochromic thinfilm is mechanically transferred on the overlying metallic layer. This sets the basis for anew nanofabrication technique.Moreover, we present near-field photodeformation effects observed in the vicinity of thenear-field probe. We show that the photomechanical response is related to both the”mechanical” interaction between the tip and the metal surface, and the photoactivityof the underlying photochromic film.In Chapter 5, we present some preliminary results on nanostructured hybrid metal/azopolymersystems and we discuss potential applications in the fields of nanofabricationin thin films and surfaces.