Potential Information and Stopping Power from Channeling in Diamond

When a carefully cleaned diamond crystal was bombarded with helium nuclei parallel to a low index plane, up to seven peaks in the energy spectrum of backscattered ions were seen. These arose from particles oscillating to and fro across the channel as they progressed along it. Spectra taken with ions incident in different directions in the same plane allowed both the wavelengths of the oscillations in the channel, ¿, and the stopping power within the channel to be obtained. The character of the oscillations changed as the beam deviated from exact alignment with the channel, giving the highest maximum at an angle ¿m to the channel. Calculations based on those of Barrett employing ¿, ¿m, and the stopping power showed a smoother potential for the {111} planar channel, which has a larger spacing, than {100} and {110}. The energy dependence of the stopping power and oscillation wavelength was also determined from 0.2 to 1.2 MeV for the {110} planar channel.