We report unprecedented transmission experiments of 3 keV Ne7+ ions through capillaries of 100 nm diameter and 10 microm length produced by etching ion tracks in a polymer foil. We studied foils tilted up to +/-20 degrees for which the incident ions are forced to interact with the capillary surface. Surprisingly, the majority of Ne7+ ions were found to survive the surface scattering events in their initial charge state. The angular distributions of the transmitted particles indicate propagation of the Ne7+ ions along the capillary axis. This capillary guiding of the Ne7+ ion provides evidence that the inner walls of the capillaries become charged and electron capture from the surface is suppressed in a self-organizing process.

We studied the dynamic properties of ion guiding through nanocapillaries in insulating polyethylene terephthalate. The angular distribution of the transmitted ions was measured as a function of the charge deposited on the sample surface, which is a measure of time. The time evolution of the angular transmission profiles was acquired for the capillary diameters of 200 and 400 nm. The tilt angle was varied from 0°to 6.5°. The transmission profiles appear as a superposition of essentially three localized peaks which exhibit significant changes in intensity as time varies. This observation provides evidence for the formation of temporary charge patches produced in the interior of the capillary besides the primary charge patch created in the entrance region.

The transmission of highly charged ions through nanocapillaries in insulating polyethylene terephthalate ͑PET͒ polymers was investigated. In experiments at laboratories in RIKEN ͑Japan͒ and HMI ͑Germany͒ different detection methods were applied to study the ion current dependence in a wide range covering two orders of magnitude. At HMI an electrostatic ion spectrometer was used and at RIKEN a two-dimensional position sensitive detector was implemented. New PET samples with parallel capillaries and low density were manufactured. For tilted capillaries, the ions are guided along the capillary axis, since the majority of ions are deflected in a charge patch created in the capillary entrance. The results provide insights into the mechanisms of capillary guiding. The fraction of transmitted ions was found to be nearly independent on the incident ion current indicating a sudden increase in the discharge current depleting the entrance charge patch. The experimental results were well-reproduced by model calculations based on a nonlinear ͑exponential͒ expression for the discharge current.

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Guided transmission of highly charged ions through nanocapillaries in insulating PET polymers was investigated. Samples with highly parallel capillaries were used to study the ion guiding with a variety of ionic species, such as Ne 7+ , Ne 9+ , Ar 9+ , Ar 13+ , and Xe 25+ . The incident energy was varied within the range of 3 − 40 keV. The fraction of transmitted ions was measured as a function of the capillary tilt angle. The results are used to evaluate the guiding angle, which is a measure of the guiding power specifying the ability of a material to guide ions. Moreover, the angular profile of the transmitted ions was studied as a function of their energy and charge state. The profile width and the guiding angle were found to follow the same scaling law indicating that they are both determined by the main charge patch in the entrance region of the capillary.