All‐optical manipulation of azo‐dye molecules

A challenging issue in the field of the design of devices for photonic applications is to achieve complete manipulation of the molecular order. Azo‐dye aromatic polymers have been shown to offer interesting prospects for material engineering using light matter interactions. Dual‐frequency irradiation using appropriate combinations of circular beams polarizations are demonstrated 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 relevant parameters of molecular translation processes is a key issue for optimization of such an optomechanical effect: a simple model accounting qualitatively for the essential features of photoinduced surface‐relief gratings will be presented.