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Charge deposition dependences of electron transmission through insulating PET nanocapillaries and a tapered glass microcapillary are reported and differences with HCI transmission are noted. Investigations were conducted for electrons with incident energies 500–1000 eV, corresponding to energies per charge similar to those used for HCI studies, incident on (1) an array of PET nanocapillaries (density ∼5 × 108/cm2) with diameters 100 nm in a foil of thickness 12 μm, and (2) on a tapered glass microcapillary with inlet/outlet diameters of 800/100 μm and a length of ∼35 mm. The transmission was measured for incident electrons at small sample tilt angles ranging from 0° to 5° with respect to the beam direction. For most angles, including those near zero degrees, there was an initial quiet period during which essentially no transmission was observed, followed by large rises in the transmission during relatively short periods of charge deposition before equilibrium of the transmission was reached. The resulting equilibrium was stable, blocked or had frequent oscillations depending on the incident energy and the capillary used. Observations for both capillaries show that a negative charge patch is needed to guide incident electrons through the capillaries similar to the manner in which HCIs are guided through capillaries.

An experimental study of electron transmission and guiding through a tapered glass capillary has been performed. Electrons were transmitted for tilt angles up to ∼6.5° and ∼9.5° (laboratory angles) for incident energies of 500 and 1000 eV, respectively. It is found that elastic and inelastic contributions give rise to distinguishable peaks in the transmitted profile. For 500 eV elastic transmission dominates the profile, while for 1000 eV both elastic and inelastic contributions are present. The transmission for both energies was studied as a function of the charge (time) deposition and found to be strongly dependent. Results suggest fundamental differences between 500 and 1000 eV incident electrons. For 500 eV the transmission slowly increases suggesting charge up of the capillary wall, reaching relative stability with infrequent breakdowns for all angles investigated. For 1000 eV for tilt angles near zero degrees the time dependent profile shows oscillations in the transmission, which never reached a stable condition, while for the larger angle investigated the transmission reached near equilibrium. Inelastic processes dominated the transmission for 1000 eV even at very small tilt angles, but was generally elastic (due to Coulomb deflection) for 500 eV even for the largest tilt angle measured.

Transmission of electrons through insulating polyethylene terephthalate (PET) nanocapillaries was observed as a function of charge deposition, angular and energy dependence. Two samples with capillary diameters 100 and 200 nm and pore densities 5 × 108/cm2 and 5 × 107/cm2, respectively, were studied for incident electron energies of 300, 500 and 800 eV. Transmission and steady state of the electrons were attained after a time delay during which only a few electron counts were observed. The transmission through the capillaries depended on the tilt angle with both elastic and inelastic electrons going through. The guiding ability of electrons was found to increase with the incident energy in contrast to previous measurements in our laboratory for a similar PET foil.

We report the experimental study of 1000 eV electrons transported through a tapered borosilicate glass capillary with inlet/outlet diameters of 800 μm/100 μm and a length of 35 mm. Transmission was observed for tilt angles from −9.5° to 1.0°. For tilt angles −9.5° to −4.5° the angular distributions of the normalized intensities of transmitted electrons consisted of a single peak showing stable transmission with inelastic behavior, while for tilt angles closer to zero (−4.0° to −1.0°) the spectrum consisted of two peaks also with an inelastic nature. Interestingly, when the tilt angle was within the range −0.8° to 0°, three peaks were observed, one being the direct peak with only elastic nature, and the other two showing both inelastic and elastic behaviors.

The charge deposition dependence and energy loss in the transmission of electrons through insulating polyethylene terephthalate (PET) were studied for incident energies of 500 and 800 eV. Charge evolution at the sample tilt angles ψ = 0.0° and −1.7° was investigated. After an initial quiescent period transmission was observed and found to reach equilibrium rather quickly. Inelastic behavior of the transmitted electrons was observed during the initial transmission as well as after reaching equilibrium for ψ = −1.7° for both incident energies.

The temporal evolution of the charge deposited by electrons during transmission through a polyethylene terephthalate (PET) nanocapillary foil was studied for incident ∼500 eV electrons at different capillary tilt angles. For all tilt angles measured there was no transmission when charge was first put on the foil, but after some time electron transmission started and then it reached equilibrium quickly. As the transmitted intensities went to equilibrium, the centroid energies of the transmitted electron distributions were found to also reach an equilibrium value.

An experimental study of 500- and 1000-eV incident electrons transmitted through a micrometer-sized funnel-shaped (tapered) glass capillary with inlet diameter 0.80 mm, outlet diameter 0.10 mm, and a length of 35 mm is reported. The properties of the electron beam transmitted were measured as a function of the emerging angle and the incident energy dependence. The angular profiles were found to be comprised of up to three peaks for both 500 and 1000 eV showing evidence for transmission going straight through the capillary without interacting with the walls (direct), as well as transmission resulting from Coulomb deflection of the electrons from a negative charge patch or by scattering from nuclei close to the surface of the capillary (indirect). The energy spectra show that elastically transmitted electrons dominate at 500 eV for increasing sample tilt angles up to \ensuremath{\sim}5.0\ifmmode^\circ\else\textdegree\fi{}, while inelastic processes dominate for 1000 eV already at tilt angles of \ensuremath{\sim}1.0\ifmmode^\circ\else\textdegree\fi{}. The angular width of the emitted electrons was found to constitute a narrow beam for direct (\ensuremath{\sim}0.4\ifmmode^\circ\else\textdegree\fi{}) and indirect (0.6\ifmmode^\circ\else\textdegree\fi{} for 500 eV and 1.0\ifmmode^\circ\else\textdegree\fi{} for 1000 eV) transmission for both energies with the widths decreasing for the largest tilt angles measured and approaching the inherent resolution (\ensuremath{\sim}0.3\ifmmode^\circ\else\textdegree\fi{}) of the electron analyzer.

The transmission of electrons with incident energies of 300, 500, and 800 eV through insulating polyethylene terephthalate (PET) nanocapillaries for small tilt angles near 0\ifmmode^\circ\else\textdegree\fi{} was studied. The exiting electrons showed elastic and inelastic behaviors with the inelasticity increasing with the tilt angle. This paper is an extension of our earlier work for electrons on PET reported by Das et al. [Phys. Rev. A 76, 042716 (2007)], but the present study goes further by investigating the transmission for very small tilt angles near 0\ifmmode^\circ\else\textdegree\fi{} with the small step sizes revealing distinct regions of behavior. The work performed here was conducted for two samples with different capillary diameters and pore densities: sample 1 with 100-nm diameter capillaries in a foil of 12-\textmu{}m thickness and a pore density of $5\ifmmode\times\else\texttimes\fi{}{10}^{8}/{\mathrm{cm}}^{2}$, and sample 2 with 200-nm diameter capillaries with the same foil thickness and a pore density of $5\ifmmode\times\else\texttimes\fi{}{10}^{7}/{\mathrm{cm}}^{2}$. Two distinct regions of transmission depending on the sample tilt angle for both samples corresponding to direct and guided electrons as well as the transition region between them were observed. The angular centers and widths of the transmission for each angle investigated were found and are discussed in terms of the tilt angle variation in the foil. For the widths, comparison with the inherent angular width of the electron spectrometer is made. Energy loss of electrons was studied from the centroids of the energy spectra with these energies corresponding to the peak centers of the angular profiles. The broadness of the energy distributions due to inelasticity was investigated from the full width at half maxima (in eV) of the spectra. The results for both samples agreed well despite the differences in capillary diameters and pore densities. The results are in partial agreement with the previous work performed for PET nanocapillaries by Das et al. [Phys. Rev. A 76, 042716 (2007)], but differences are also found.

Transmission and guiding of electrons traveling through insulating PET nanocapillaries were measured for different sample tilt angles at the energies of 500 and 800 eV. Direct transmission and guiding and the transition between the two regions were observed for angles near zero degrees. Elastic and inelastic spectra and a combination of the two were seen in the different regions.

The transmission of electrons through a tapered glass capillary was observed for 1000 eV incident electrons up to tilt angles of ~9.5°. Tilt angle dependence of the energy loss broadening shows clear correspondence of elastic and inelastic processes. Both were found for smaller tilt angles.

The transmission of 1 and 3 MeV protons through a borosilicate straight glass capillary and a tapered glass capillary was investigated. The straight capillary had a diameter of ~0.18 mm and a length of ~14.4 mm, while the tapered capillary had an inlet diameter of ~0.71 mm, an outlet diameter of ~0.10 mm and a length of ~28 mm. The results show that the 1 and 3 MeV protons traverse through both samples without energy loss, while the tapered capillary showed better transmission than the straight capillary.

Transmission of electrons through a polycarbonate nanocapillary foil with diameter 200 nm and aspect ratio ~ 40 has been studied at energies 500 and 1000 eV. The direct transmission of electrons was observed for both energies while onset of guiding was observed for 500 eV. Time (charge) evolution measurements were also carried out at different sample tilt angles.

Transmission of 3 MeV protons and 16 MeV O5+ ions through a single glass macrocapillary and a polycarbonate nanocapillary foil has been investigated. Results show that 3 MeV protons transmit through the capillary and the foils with little or no energy loss, while 16 MeV O5+ ions show transmission through the capillary and the foil with energy losses that vary with the tilt angle, and there are also changes in the charge state.