A5033661990- Laser-induced spectroscopy and plasma
- Atomic and Molecular Physics
- X-ray Spectroscopy and Fluorescence Analysis
- Laser-Plasma Interactions and Diagnostics
- Laser-Matter Interactions and Applications
- Advanced Fiber Laser Technologies
- Precipitation Measurement and Analysis
- Radio Wave Propagation Studies
- Millimeter-Wave Propagation and Modeling
- Plasma Diagnostics and Applications
University College Dublin
2015-2021
Queen's University Belfast
2021
Rutherford Appleton Laboratory
1987
Lithography tools are being built and shipped to semiconductor manufacturers for high volume manufacturing using extreme ultraviolet lithography (EUVL) at a wavelength of 13.5 nm. This is based on the availability Mo/Si multilayer mirrors (MLMs) with reflectivity ∼70% this wavelength. Moreover, primary tool manufacturer, ASML, has identified 6.x nm, where x∼7, as choice so-called Beyond EUVL, La/B4C MLMs, theoretical reflectance approaching 80% The optimum sources have been laser produced...
Soft x-ray emission spectra of dysprosium, erbium and thulium ions created in laser-produced plasmas were recorded with a flat-field grazing-incidence spectrometer the 2.5–8 nm spectral range. The produced using an Nd:YAG laser 7 ns pulse duration at various power densities. experimental interpreted aid Cowan suite atomic structure codes flexible code. At wavelengths above 5.5 are dominated by overlapping n = 4 − unresolved transition arrays from adjacent ion stages. Below 6 nm, 5...
A 500 m experimental range which has been constructed to carry out propagation studies at millimetre, infra-red and optical wavelengths is described. The a well- instrumented open-air laboratory where the transmissions are monitored simultaneously with comprehensive set of meteorological measurements obtain data required develop prediction models use in design future communications systems. Some examples given attenuation rain, snow fog, effects scintillation.
Abstract Spectra of laser-produced plasmas cerium have been recorded in the 1.5 to 15.5 nm spectral region. The were formed using frequency doubled pulsed output a neodymium-doped yttrium aluminium garnet (Nd:YAG) laser at 532 nm. At power densities incident on-target, ranging from 8.6 × 10 9 –2.1 13 W cm −2 , Ce 4+ 27+ ions gave rise emission Δ n = 0, 1 transitions final states where 4. spectra are dominated by an intense unresolved transition array (UTA) 8–10 region arising 4 transitions....
Abstract Laser driven high harmonic generation from relativistically oscillating plasma surfaces is a promising route to isolated attosecond pulses with peak brightness. Here we investigate double optical gating scheme restrict the emission only single, intense, pulse even multi-cycle driving laser. This scheme, which uses second field, combined pair of counter-rotating circularly polarized laser pulses, leads more efficient improved temporal isolation when compared single colour polarization scheme.
We have observed extreme ultraviolet (EUV) spectra from terbium (Tb) ions in optically thin and thick plasmas for a comparative study. The experimental are recorded thin, magnetically confined torus dense laser-produced (LPPs). main feature of the is quasicontinuum emission with peak around 6.5-6.6 nm, bandwidth which narrower than LPPs. A comparison between two types also suggests strong opacity effects calculated line strength distributions gives qualitative interpretation spectra.
Much effort has gone into the development of plasmas as sources radiation in 2 to 9 nm region recent times with particular interests "water window" (2.3 4.4 nm) and 6.X region. Plasmas were formed on a range targets medium high atomic number (Z) elements using Nd:YAG lasers various illumination parameters. Spectra recorded 0.25 m grazing-incidence spectrograph spectral analysis was carried out aid Hartree-Fock configuration interaction calculations Cowan suite codes [1].