Reachable Extreme Ultraviolet Wavelengths According to Elements / Atomic Data

Extreme ultraviolet and soft X-ray sources have been identified, using the FAC relativistic code, as emission arising from 4d–4f and 4p–4d transitions in palladium-like to rubidium-like ions of lanthanum through actinium. The spectra of these strong emitters are seen to separate and move to shorter wavelength as the nuclear charge increases. The emission was comparable from each source and was characterized using the unresolved transition array model. In future applications such as microscopy, spectroscopy and lithography, these radiation sources may be generated by employing the laser-produced plasma technique.