Experiments and simulations of ion guiding through nanocapillaries in insulating polymers

Recent experimental studies of dynamic properties concerning ion guiding through nanocapillaries etched in polyethylene terephthalate (PET) and polycarbonate (PC) are reviewed. The temporal evolution of the intensity and the angular distribution of the transmitted ions have been measured as function of the charge inserted into the capillaries. The mean emission angle exhibit pronounced oscillatory structures both for PET and PC. The experimental results are interpreted by simulations of the ion trajectories guided in 3 dimensions by the electrostatic field within the capillaries. This field was determined from the charge deposited at the walls of the capillaries taking into account the transport of the charges by means of the surface conductivity. The experimental oscillations of the mean emission angle are well reproduced by the simulations. Differences between results using PET and PC are attributed to differences in the surface conductivity.