Ion-matter interaction: the three-dimensional version of the thermal spike model. Application to nanoparticle irradiation with swift heavy ions

In the framework of swift heavy ion-matter interaction, the thermal spike has proved its worth for nearly two decades. This paper deals with the necessary refinement of the computation due to the kind of materials of interest, i.e. nanomaterials such as multilayered systems or composite films constituted of nanocylinders or nanospheres embedded in an insulating matrix. The three-dimensional computation of the thermal spike model is applied for the first time in the case of ions striking layers containing spherical nanoparticles embedded in a silica matrix. The temperature profiles calculated at each point (x, y, z) of the target for a total duration up to 10(-10) s and different values of ion impact parameter allow a possible explanation of the particle shape change under irradiation with swift heavy ions having an energy of several MeVamu(-1)