Basic mechanisms of the femtosecond laser interaction with a plasmonic nanostructure in water

This paper presents a complete partial differential equation based model to describe the interaction of an ultrafast laser with a plasmonic nanostructure in water. Apart from heating the structure itself, it is shown that this interaction also leads to the generation of a plasma in the water medium and to the production of a strong pressure wave and a nanobubble in the vicinity of the structure. Plasma collisions and relaxation are shown to be the main source of mechanical stress in the medium and the dominant factor for the pressure wave and bubble creation. An all-optical technique able to detect plasmonic enhanced bubble formation and pressure wave generation is also presented.