Déformation photoinduite dans les films minces contenant des ...

Conclusions 153timelight ON" # 800 nmpolarizationswitchFigure ! 5.11: Reversible, oscillating actuation: a potential application.pastel-00527388, version 1 - 19 Oct 2010using near-field probe-sample photomechanical interactions, which sets the basis for newnanofabrication techniques. It also demonstrates that the photo-induced deformation ofthe photoactive layer is capable of performing a mechanical work on an overlying layer.The improved knowledge on the origin of the matter migration phenomena, the demonstrationof the reversible, directional matter transport obtained by switching the polarizationof the light and the demonstrated capability of the photo-induced deformationto perform mechanical work on other bodies open the way to an innovative potentialapplication of the photodeformation phenomena. For instance, it is possible to producea reversible oscillating surface deformation addressing simultaneously nanometric featuresover the entire illuminated surface. Each oscillating structure produces a verticaldisplacement and a vertical force, which can be transmitted to overlying objects, as itis demonstrated with the vertical motion of gold nanoparticles in section 5.1.In Figure 5.11 we illustrate the principle on a single working unit. On the surface, acouple of nano-rods is linked to a nano-wheel, which is actuated by the surface deformationthrough a transmission provided by the nano-rods. Latest results in the field ofthe micro-nano machining demonstrate the possibility to fabricate components in thesub-micron range, as reported, for example, in ref. [1] where supra-mulecular architecturesof platinum(II) complexes having the shape of rods and wheels of the order of200 ÷ 800 nm have been obtained.At t = 0 the surface is flat. Illuminating with an interference pattern induces the growthof SRG, which can be reversed switching the polarization of the light, providing lightdriven,reversible actuation of the wheel. We can think of a parallel architecture, wherereversible movement is optically induced on a large surface of working units. Indeed, thisapplication constitutes an interesting new technique of light driven parallel actuation atmicro-nanoscale.