Showing papers by "David Goodstein published in 1994"
TL;DR: The peak in the energy spectra that corresponds to collisions in which the Cu atom interacts primarily with a single Cu atom is studied, demonstrating that the TA can fail when recoil is substantial.
Abstract: We have scattered low energy (100-400 eV) ${\mathrm{Na}}^{+}$ from a Cu(001) surface, and studied the peak in the energy spectra that corresponds to collisions in which the ${\mathrm{Na}}^{+}$ interacts primarily with a single Cu atom. This peak is broadened by the thermal fluctuations in the momentum of the Cu atom. Its width has been measured as a function of surface temperature, scattering geometry, and incident energy. Our data agree well with a rigorous statistical analysis (within 10%) but poorly with the trajectory approximation (TA), demonstrating that the TA can fail when recoil is substantial.
11 citations
TL;DR: In this paper, the authors measured the temperature-dependent energy broadening (ΔE)2 of the quasisingle scattering peak for Na+ ions scattering from a Cu(001) surface, and found it to agree with a parameter-free theoretical prediction to within 10%.
Abstract: In recent experiments, we have succeeded in measuring thermal momentum fluctuations of surface atoms using hyperthermal (E<500 eV) energy ions. These fluctuations lead to a broadening of the energy loss peaks observed in ion surface scattering experiments. Specifically, we have measured the temperature-dependent energy broadening (ΔE)2 of the quasisingle scattering peak for Na+ ions scattering from a Cu(001) surface, and found it to agree with a parameter-free theoretical prediction to within 10%. We point out that at lower temperatures than those of the present experiment, and with no detailed knowledge of the ion surface potential, this peak should yield quantitative information about the surface lattice dynamics.
3 citations