The EUV Generation and Imaging group at ARCNL focuses on optimization and understanding of 13.5 nm wavelength production from laser-generated plasmas. To achieve this goal, we study the fundamental physics underlying the laser-driven plasma formation, ionization and plasma dynamics, and subsequent EUV emission from the hot plasma. An important tool is time-resolved spectroscopy with a variety of advanced ultrafast laser sources, ranging in wavelength from the infrared to the extreme-ultraviolet. To generate these wavelengths, and to control the plasma, we use a combination of high-power laser amplifier systems (optical parametric chirped pulse amplification), high-harmonic generation, and pulse shaping methods.
In addition, we are working on novel methods for EUV imaging and microscopy, to investigate nanoscale structures at unprecedented resolution and contrast. In this research project we employ coherent EUV and soft-X-ray radiation produced through high-harmonic generation, which we use for lensless coherent diffractive imaging of the structures under study. High-resolution images of the object are then obtained numerically, using e.g. iterative phase retrieval algorithms. Such an approach means that imaging is no longer limited by the quality and even the availability of optical elements. This is particularly promising for phase-sensitive ultra-high-resolution imaging over wide wavelength ranges in the EUV.