ELLIPTIC POLARIZATION FROM GRAZING-INCIDENCE COLLISIONS OF HYDROGEN-IONS ON POLYCRYSTALLINE AND SINGLE-CRYSTAL SURFACES

Strong elliptic polarization has been observed in Balmer radiation (Hα, 656.3 nm) following low-energy grazing-incidence collisions of H-, H+, H2+2, and H+3 on a clean lead polycrystalline surface and on a clean nickel single crystal (110) in all cases maintained under ultrahigh vacuum. In explanation of the basic phenomenon a two-step surface-interaction model is presented based on anisotropic near-resonant electron pickup followed by quantum mechanical phase evolution. The influence of a single crystal target surface on the intensity and polarization of the radiation is discussed. © 1979.