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arXiv · 2505.13075

Tabletop Lensless Imaging in the Extreme Ultraviolet with Reduced Radiation Dose

Sukyoon Oh·Monalisa Mallick·Thomas Siefke·Christian Spielmann
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Abstract

High-resolution extreme ultraviolet (XUV) imaging remains limited by conventional approaches that require complex optics such as multilayer mirrors and zone plates. These methods are expensive, suffer from chromatic aberrations and narrow fields of view, and demand highly stable, coherent beam sources typically found only at large-scale facilities. Critically, the high photon flux they require often damages sensitive biological and soft-matter samples. We present a new solution: a lensless XUV microscopy platform combining a compact tabletop high-harmonic generation source with correlation-based ghost imaging. Our approach eliminates the need for complex optics, lowering system cost and dramatically improving resilience against lab-scale instabilities. Leveraging Hadamard patterns and compressive sensing algorithms, we achieve high-fidelity imaging even in low-photon environments, with a 400\% improvement in structural similarity index compared to baseline methods. This confirms the feasibility of broadband, low-dose XUV imaging, enabling damage-minimized, non-destructive inspection for advanced materials and biological specimens, and establishes a new paradigm for accessible XUV microscopy.

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Sukyoon Oh, Monalisa Mallick, Thomas Siefke, Christian Spielmann. 2025-11-13. Tabletop Lensless Imaging in the Extreme Ultraviolet with Reduced Radiation Dose. https://arxiv.org/abs/2505.13075

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