The shaping and focusing of a Ne⁷⁺ ion beam by transmission through an array of nanocapillaries of rectangular cross section in mica is studied both by experiments and simulations. The transmitted angular profiles of the beam are measured as they develop with charging-up the rectangular capillaries by ion impact and compared with rhombic capillaries of different parameters in mica. Thereby it is found that the profiles after transmission through rectangular capillaries degrade with charging them up. This is in contrast to our previous findings [Phys. Rev. A. 86, 022,901 (2012)] with rhombic capillaries, where the transmitted angular profiles only shift by charging-up. The reasons for that and the features of the tailored shapes of the transmitted ion beams will be discussed here, supported by simulations.

We report on an unexpected effect of tailoring transmission profiles of Ne7+ ions through nanocapillaries of rhombic and rectangular cross sections in mica. We find that capillaries of rhombic cross sections produce rectangular shaped ion transmission profiles and, vice versa, that capillaries of rectangular geometry give a rhombic beam shape. This shaping effect only occurs for transmitted ions and is absent for the small fraction of neutralized particles. The experimental findings and simulations of the projectile trajectories give clear evidence that the observed effect is due to the image forces experienced by the transmitting ions. This novel beam shaping mechanism suggests applications for the guiding, focusing, and shaping of ion beams.

The angular distributions of Ne7+ ions transmitted at various kinetic energies of 7-70 keV through muscovite mica nanocapillaries of rhombic cross section are measured. It is found that the transmitted ion beams form a rectangular shape at tilt angles that are small compared to those given by the aspect ratio, i.e., the capillary geometrical opening angle. This shape is retained for all ion energies, but its size changes. The time evolution of the transmitted angular distributions shows that the characteristic profile occurs instantaneously and remains in the stationary state of the transmission, whereas it shifts with the increase of the accumulated incident charge. At tilt angles of the capillaries larger than their aspect ratio, the shape in the transmission profile gets distorted from the rectangle by the deposited charge. Combined with trajectory simulations we show the observed shaping effect is due to the image force seen by the ions, interplaying with a deflection by the deposited charge on the capillary walls.

Transmission properties of slow highly charged ions through nanometer thick foils are discussed.  We also report on the measurement of the energy loss and the charge states of 46.2 keV Ne¹⁰⁺-ions and 11.7 keV Ne³⁺-ions transmitted through ultra-thin carbon nano-sheets. The sheets had a thickness of 1.2 nm (single molecular layer) and 3.6 nm (three molecular layers). The measured energy loss of the transmitted ions is considerably smaller than the calculated energy loss by SRIM but it is in agreement with energy loss calculated using the Firsov model. The majority of the transmitted ions retain their initial charge state (up to 98%) contrary to prediction by the classical over-the-barrier model. The results suggest that the energy loss of slow highly charged ions in such thin sheets is only due to the electronic excitations, without charge exchange inside the target.

Time evolution of angular distributions of transmitted ions through SiO2 nanocapillaries wasmeasured under defined initial conditions: already charged, as well as fully dischargedcapillaries. We find distinct charge patterns and describe them quantitatively with the help of amodel calculation. This results in a pattern of a few number of charge patches, guiding ions inthe stationary state of transmission. For the already charged capillary membrane, we show a“memory effect” in the form of a double peak structure in the transmitted angulardistributions. The time evolution of these structures reflects charge relaxation andrearrangement of the charge patches. The re-arrangement of the charge patches is much fasterthan the discharge, suggesting that the charge relaxation inside the capillaries can be drivenby the incident charges, such as a Frenkel-Poole process.

This thesis contains experimental work on guiding of highly charged ions through insulating nanocapillaries. We have studied the time evolution of angular distributions of transmitted ions under well defined initial conditions: already charged, as well as fully discharged nanocapillaries, by using a two-dimensional position sensitive Micro Channel Plate detector with a data acquisition system working in event mode. Time-dependent features in the ion-guiding properties have been found. For the initially discharged capillaries, a shift and broadening of transmitted angular distribution have been observed in the charge-up process. This is interpreted by the formation of charged patches downstream of the entrance patch. We have, with the help of a model calculation, quantitatively derived distinct charge patterns, resulting in the time evolution of the transmitted angular distributions. We show that all charge patches are maintained in the stationary state of transmission by the followed discharging and recharging measurements. For already charged nanocapillaries, a double peak structure in the angular distribution has been found, which is attributed to a memory effect and the re-arrangement of charge patches. When the tilt angle of the capillaries is changed, the existing charge patches from the previous tilt angle can affect the ion trajectories and the formation of new patches.

The preliminary results of highly charged ions transmitted through muscovite mica capillaries of rhombic cross section are also presented in this thesis. We have shown the transmission profiles for various orientations of the rhombi. A rectangular shape of the transmission profile has been found. We have performed a simulation by considering the image force from the four sides of the rhombus. To our surprise, this effect gives an angular distribution that agrees well with the transmission profile obtained by the experiment.

A new laboratory for highly charged ions is being built up at Stockholm University. A fully refrigerated electron beam ion trap (R-EBIT, 3 T magnet, 30 keV electron energy) was installed. It was used for spectroscopic studies, ion cooling experiments, electron ion collisions, and highly-charged ion surface studies. Here we report on an upgrade of this EBIT to a ``Super EBIT'' (S-EBIT, 4 T magnet, 260 keV electron energy). The high-voltage trapping system, the ion injection as well as the extraction scheme of S-EBIT and the LabView based operational system of S-EBIT are described.

The guiding of highly charged ions through SiO₂ nano-capillaries has been investigated by our group, using 7 keV Ne⁷⁺-ions. We studied in particular the transmission of ions incident at angles greater than the angle given by the capillary aspect ratio as a function of charge incident on the capillary membrane. In this report we show the re-arrangement of charge patches inside the capillary by observing the evolution of the two-dimensional angular distributions of the transmitted ions.

We investigated the time evolution of the dynamically shifting distribution of 7 keV Ne⁷⁺ ions guided through nanocapillaries in SiO₂. We present evidence for a small number of charge patches, formed sequentially in the charging-up process, guiding the ions. We show that the charge patches are distributed along the whole length of the capillaries and that they are maintained in the equilibrium state of transmission. The interpretations are supported by model calculations.

The guiding of highly charged ions through nanocapillaries in different insulating materials, such as polyethylene terephthalate, SiO₂, and Al₂O₃ has been investigated by our group, using 7 keV Ne⁷⁺ ions. We find transmission of ions incident at angles larger than the angle given by the capillary aspect ratio in all these materials. The measured angular distributions, however, vary with the membrane material. In this report we compare the experimental findings with the different membranes.