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Three-dimensional metallodielectric photonic crystals were created by fabricating a micron-scale polymeric template using multiphoton direct laser writing (DLW) in SU-8 and conformally and selectively coating the template with copper (Cu) via nanoparticle-nucleated electroless metallization. This process deposits a uniform metal coating, even deep within a lattice, because it is not directional like sputter-coating or evaporative deposition. Infrared reflectance spectra show that upon metallization the optical behavior transitions fully from a dielectric photonic crystal to that of a metal photonic crystal (MPC). After depositing 50 nm of Cu, the MPCs exhibit a strong plasmonic stop band having reflectance greater than 80% across the measured part of the band and reaching as high as 95% at some wavelengths. Numerical simulations match remarkably well with the experimental data and predict all dominant features observed in the reflectance measurements, showing that the MPCs are structurally well formed. These data show that the Cu-based process can be used to create high performance MPCs and devices that are difficult or impossible to fabricate by other means.

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There is tremendous demand for numerical methods to perform rigorous analysis of devices that are both large scale and complex throughout their volume. This can arise when devices must be considered with realistic geometry or when they contain artificial materials such as photonic crystals, left-handed materials, nanoparticles, or other metamaterials. The slice absorption method (SAM) was developed to address this need. The method is fully numerical and able to break large problems down into small pieces, or slices, using matrix division or Gaussian elimination instead of eigensystem computations and scattering matrix manipulations. In these regards, the SAM is an attractive alternative to popular techniques like the finite-difference time domain method, rigorous coupled-wave analysis, and the transfer matrix method. To demonstrate the utility of the SAM and benchmark its accuracy, reflection was simulated for a photonic crystal fabricated in SU-8 by multiphoton direct laser writing. Realistic geometry was incorporated into the model by simulating the microfabrication process, which yielded simulation results that matched experimental measurements remarkably well.

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A new method to produce a model system for the study of radiation damage in non-radioactive materials is presented. The method is based on homogenously dissolving minute amounts of 228Th ions in thin films in a controllable manner using a small volume chemical bath deposition technique. This approach is demonstrated for PbS films. The properties of the PbS (228Th) solid solution film activity were investigated by monitoring the accompanying radioactive processes. Electrical resistivity studies were performed and decay-event damage accumulation was measured, followed by isochronal annealing which presented two annealing stages and another two sub-stages. This is the first report on self-irradiating damage studies in IV-VI semiconductors and the resulting films present a novel method for the analysis of dilute defect systems in semiconductor thin films.

The practical application of a polycarbonate as a dosimeter for high energy neutrons is presented. The efficiency of this dosimeter in the energy range of 1-14 MeV was measured with monoenergetic neutrons produced by the 'Li(p, n) 'Be and t(d, n) 4He reactions and with neutrons from 25ZCf and Z39P~-Be sources.The electrochemical etching technique for enlarging the damage sites produced by the neutrons, the background of unirradiated polycarbonate foils and the dose thresholds for various energies were investigated. The replacement of the conventional emulsion dosimeter by the polycarbonate dosimeter in the Israel National Badge Service is described.

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