No abstract available

[en] A Penning trap which is optimized for transverse resistive cooling yields a cooling time constant for trapped He⁺ ions of as low as 3 seconds, depending on cooling duty cycle. Opposite quadrants of the ring electrode resonate (Q=1800 at 7.4 MHz) with Nb/Ti inductors at 4.2 K. The f' motion is resonantly cooled by operation at 2 Tesla axial field and trap voltages from 12 to 38 Volts. Ion signals are magnetically coupled to a 4 K GaAs fet preamplifier, wide-band 300 K amplifier and linear diode detection system. The rate of cooling is set by fractional time on resonance during sweep of the trap voltage. Shifting and broadening due to space charge are demonstrated. Other interesting features of the ion spectra, such as peak structure, response to heating by f⁺ - f^-, and growth/decay of the peak components, will be presented

No abstract available

No abstract available

[en] The results reported give evidence of a high energy desorption peak which exhibits a rapid growth when the quantity of helium, trapped in the tungsten at energies higher than 400eV, is increased. The presence of this peak can be explained by the migration of vacancies containing helium atoms, leading to the formation of microbubbles of gas in the metal

No abstract available

No abstract available

No abstract available

[en] The method of complex-coordinate rotation is used to investigate resonances in e⁺-He⁺ scattering. By using Hylleraas-type wave functions the auhor has obtained resonance positions and widths for two S- and two P-wave resonances. The resonance positions for the two S-wave states are consistent with those obtained by Bhatia and Drachman who used the stabilisation method. The total widths for the lowest S- and P-wave resonances are determined in the present work as 3.52 eV and 4.83 eV, respectively, raising the possibility that such resonances may be detectable in e⁺ - He⁺ scattering experiments

[en] Carbon nanotube nanogaps have been used to contact individual organic molecules. However, the reliable fabrication of a truly nanometer-sized gap remains a challenge. We use helium ion beam lithography to sputter nanogaps of only (2.8 ± 0.6) nm size into single metallic carbon nanotubes embedded in a device geometry. The high reproducibility of the gap size formation provides a reliable nanogap electrode testbed for contacting small organic molecules. To demonstrate the functionality of these nanogap electrodes, we integrate oligo(phenylene ethynylene) molecular rods, and measure resistance before and after gap formation and with and without contacted molecules