New-generation electronic, quantum, and semiconductor devices are becoming increasingly complex and continuously shrinking in size. Characterizing such structures at the nanoscale requires imaging techniques that combine extremely high spatial resolution with sensitivity to material composition. Extreme ultraviolet (XUV) ptychography is a highly promising microscopy technique capable of meeting these requirements. However, current tabletop XUV ptychographic microscopes still face significant challenges in terms of spatial resolution, robustness, and available photon flux.
The Extreme Ultraviolet Ptychographic Microscopy (XUVPM) project aims to address these challenges by developing novel structured illumination sources for XUV ptychography. The core approach is based on high-order harmonic generation (HHG), driven by tailored laser beams, to create structured XUV beams with controllable spatial properties. In particular, the project explores the use of light carrying orbital angular momentum (OAM) as illumination for ptychographic microscopy. Such structured light is expected to improve the robustness of image reconstruction and enhance spatial resolution.
To realize this vision, the project combines expertise in ultrafast optics, HHG, structured light, and computational imaging. A two-color HHG setup was established, enabling flexible control of the driving laser beams through individual spatial light modulators (SLMs). The generated XUV radiation was then intended to be integrated into a newly designed ptychographic microscope.
During the course of the project, some methodological aspects were adjusted in response to scientific findings. Nevertheless, the overall objective remained unchanged: to advance the tabletop XUV ptychographic microscopy through the development and investigation of novel structured XUV illumination schemes. In the long term, the knowledge generated by this project is expected to contribute to future imaging solutions for advanced semiconductor and quantum technologies, while strengthening Europe's leadership in attosecond science and high-resolution microscopy.
