All-optical manipulation of azo-dye molecules

A challenging issue in the field of the design of devices for photonic appl ications is to achieve complete manipulation of the molecular order. Azo-dy e aromatic polymers have been shown to offer interesting prospects for mate rial engineering using light matter interactions. Dual-frequency irradiatio n using appropriate combinations of circular beams polarizations are demons trated to enable full control of the molecular polar rotation. More recent results on photoinduced surface-relief gratings have also opened the way of molecular translation control using optical fields. Understanding of the r elevant parameters of molecular translation processes is a key issue for op timization of such an optomechanical effect: a simple model accounting qual itatively for the essential features of photoinduced surface-relief grating s will be presented.