A thermal-energy beam of Xe(nf) Rydberg atom has been utilized to study electron tunneling during atom/surface interactions. The Xe Rydberg atoms, which are created by laser-induced photoexcitation of Xe(3P 0) metastable atoms, are incident at near grazing angle on a flat Au(1 1 1) surface. At some critical distance, the Rydberg electron will tunnel ...

This thesis demonstrates that strongly polarized quasi-one-dimensional very-high-n potassium Rydberg atoms can be produced by photoexcitation of selected Stark states in the presence of a weak dc field. Calculations show that, for m = 0 states, significant photoexcitation occurs only in the vicinity of the Stark-shifted s, p, and d levels, and that ...

Dissociative electron attachment to CFCl$\sb3$, CF$\sb2$Br$\sb2$, and 1,1,1- and 1,1,2-C$\sb2$Cl$\sb3$F$\sb3$ is studied by measuring the velocity and angular distributions of negative ions produced through electron transfer in collisions with velocity selected K(np) Rydberg atoms. Data analysis is done with the aid of Monte Carlo simulations. ...

The resonant ionization of Xe(nf) Rydberg atoms in extreme red and blue Stark states at a conducting surface is investigated. The Xe( nf) Rydberg atoms are created by laser induced photoexcitation of xenon 6s'[1/ 2]0 metastable atoms created within a DC discharge. Following ionization the resulting Rydberg ion core is attracted to the surface by its ...

Electron transfer in collisions between atoms in high Rydberg states and polar targets can lead to the formation of dipole-bound negative ions in which the excess electron is weakly bound by the dipole potential of the neutral molecule. Their lifetimes and collisional destruction rates are studied using a Penning ion trap. Ion decay in the trap is ...

The design and characterization of an intense source of metastable Ar(3P0,2) atoms is described together with its application in the patterning of Si surfaces. Two different approaches to patterning were investigated. In the first, a hydrogen-passivated Si(100) surface was exposed to the Ar(3P0,2) metastable atom beam, in the presence of a small ...

Spin-polarized ion neutralization spectroscopy (SPINS), in which a beam of electron-spin-polarized He+ ions is directed onto a surface and analysis is done of the electrons ejected from the surface as a result of ion neutralization, is a unique tool for surface studies that has unparalleled surface specificity. This technique has been used in studies ...

An apparatus has been developed for studying the interaction of Rydberg atoms with surfaces, particularly the perturbation of Rydberg states by a nearby surface and the distance from the surface at which resonance ionization occurs. For this purpose, a source of metastable Xe(3P 0,2) atoms was constructed and characterized. Using single photon laser ...

A spin polarized He$\sp+$ ion source has been developed to study the dynamics of ion-surface interactions. The He$\sp+$ ions are produced by Penning ionization in collisions between electron-spin-polarized He(2$\sp3$S) metastable atoms contained in a weak rf-excited discharge. The ions are extracted from the discharge and focused onto clean or ...

Mott polarimeters are used in many areas of physics to determine the spin polarization of electrons in studies of processes dependent on the electron's intrinsic spin angular momentum and associated spin magnetic moment. Mott polarimeters work by measuring the left-right asymmetry in the spatial distribution of electrons scattered from high-Z nuclei. ...