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The robustness of the hole target against laser parameter changes in a laser spot size and in a laser pulse length against a contaminated proton source layer and against a laser alignment error are described. The multiple-hole target is robust against a laser alignment error and a target positioning error and it has served as a robust target for practical uses to produce a collimated proton beam.

Anomalous field enhancement occurs between two-plasmon-resonant surfaces. This model is expected to be useful for metal surfaces having roughness.

Research into void dynamics in relation to the critical morphological evolution is presented. This work was designed to identify the circumstances under which premature failure of metallic thin interconnects arises. The significance of the surface diffusion anisotropy for the premature creation of a fatal open circuit configuration is highlighted.

A study was conducted to analyze electron transport in an atom-sized bridge between a metal surface and a tip of a scanning tunneling microscope. The perturbation technique was utilized to determine the self-energy against the Coulomb interaction within a single-site approximation. The electric current was then obtained by solving the Lippmann-Schwinger equation. Experimental results indicated that increases in temperature dependence correlated with the strength of the Coulomb interaction.

Conductivity and permeability vary as a function of depth in the near-surface region in the frequency-dependent impedance of right-cylindrical air-core eddy-current probes over thick metal plates. An impedance analyzer was used to measure the probe impedance from 1kHz to 1MHz. The theory was tested by using precision-wound air-core coils, and industrial practice was connected to commercial eddy-current probes. Uniform plates of metals, covered with many thin, discrete layers of other metals and core-hardened titanium plates with smoothly and continuously varying near-surface conductivity as a function of depth, were used to model a continuous profile. Stacking many thin layers with differing conductivities can simulate continuous profiles, and the conductivity change affects the probe in impedance change.

The permeation processes in the bulk, the surface/bulk and gas/surface interfaces which affect hydrogen transport in metals were investigated using models. The results showed that the permeation process was characterized by three distinct mechanisms: rate limiting absorption upstream, rate limiting desorption downstream and bulk saturation. Permeating flux saturation brought about by rate limiting absorption upstream occurred at pressures greater than that required in saturation of upstream surface coverage.

The effects of low energy bombardment of a Cu surface by Cu atoms were investigated using molecular-dynamics simulations. The results showed that vacancies were formed only near the surface while interstitials were produced further inside. The bombarding energy greatly detrmined the degree of defect production. The amount of interstitials was significantly decreased by changing the perpendicular incidence.

Ascanning tunneling microscopewas used to assist the growth of nanometer-scale uniform gold stripes on reconstructed Au(111) surfaces. The microscope tip was used to produce stripes several 100 nm in length and separated by spaces ranging from two to four nm. Stripes were formed only when the scan direction was towards the direction of reconstruction. The growth was observed to be faster than that seen in diffusion alone.

A study was conducted on the use of the relaxation method in determining surface crack size and shape in metallic structures. The approach is entirely numerical in nature and uses measurements taken from the crack vicinity itself. Synthetic input and noisy data were used in the study. The alternate current potential difference technique was used as a basis for the new approach.

Functionally graded multiferroic composites are examined in order to design the electromagnetic properties of synthetic surface and material surfaces. The results have shown that the amplitudes of the field response along the direction of the compositional gradient can be either matched to a uniform material or systematically reduced and Green's functions are used for studying the electric dipole-induced electric and magnetic potentials in the graded multiferroics.

Several studies are conducted to explain the surface charge induced variations observed in the electrical conductivity of nanoporous gold during the charging and decharging of the metal surface. The effective thickness of the ligands is also shown to highly affect the conductivity of the metal.

The scheme of electron acceleration that has used resonant interaction of electrons with a surface plasma wave is used in accelerating electrons to higher energies with the control in their trajectories. The configuration of two parallel surfaces separated by a vacuum region has supported a surface plasma wave that has propagated parallel to the metal surfaces with amplitude maxima on the two surfaces and a minimum in the middle.

Ray tracing using Nd:YAG laser is used to study the absorption of light by smooth and rough surfaces. The results show that in light incident at a tangent to the surface, the absorptance is found to rise, fall, and rise again with increase in surface roughness due to multiple scattering.

The scanning electron microscope analysis has shown that nanoholes of approximately 25-50 nm in diameter, arranged in one-dimensional (1D) and two-dimensional (2D) irregular and regular arrays, are formed. The results conclude that nanoporosity can be generated on metal surfaces by nanosecond laser-matter interactions in the semi-confined configuration.

The characteristics of luminescence that is induced by high-velocity impacts of metallic particles on metal surface are analyzed. The analysis has shown that the intensity of luminescence depends not only on the energy of the impinging particles and on the stresses produced on impact but also on the particular combination of materials and of the particles and the plate.

The basic characteristics of the near-field intensities of the proposed I -shaped aperture in the pyramidal structure is investigated which would provide high emission intensity and small spot size simultaneously. It was found that the I-shaped aperture in the pyramidal structure had a higher near field intensity and much smaller spot size than those of conventional simple square aperture.

The molecular dynamics simulations are used to investigate the ion beam induced smoothening of crystalline and amorphous substrates. Low energy recoil events in an amorphous substrate lead to the sinking of a nanoparticle indicating that thermal spikes are not required for radiation-induced viscous flow.

Investigation was carried out on the molecular orientation dependence of the o-p conversion of H(sub 2) interacting with a metal surface and the conversion yield for a perpendicular orientation is larger than that for a parallel orientation. The results not only show a strong dependence on the orientation of the H-H bond with respect to the surface, but also on the H(sub 2) c.m. distance from the surface.