Interaction of slow highly charged ions with the inner surface of nanocapillaries

The transmission of 1-10 keV Ne7+ ions through nanocapillaries in a highly insulating PET polymer was studied. Capillaries with a diameter of 100 nm and a length of 10 μm in PET were produced using chemical etching techniques. For slow projectiles the angular distributions of the transmitted ions show that they are predominantly transported in their initial charge state along the capillary axis even when the capillaries are tilted with respect to the incident beam direction. This result indicates ion-guiding, which is produced by charge-up effects influencing the ion trajectories in a self-supporting manner. Emphasis is given to results studying the projectile-energy dependence of the capillary guiding. A relatively strong energy dependence is observed for the fraction of guided ions. Guiding effects for the studied Ne7+ ions are found to diminish at projectile energies above about 10 keV.