Physicist Fengling Zhang studied the development of multi-wavelength extreme ultraviolet (EUV) ptychography for high-resolution, lensless imaging at the nanoscale.
A tabletop high-harmonic generation (HHG) source is implemented to provide coherent and spectrally tunable EUV illumination. The work advances ptychographic reconstruction techniques by introducing structured and multi-wavelength illumination to enhance phase retrieval robustness and spatial resolution. Material-sensitive and thickness-resolved imaging is demonstrated through spectrally resolved measurements, enabling quantitative analysis of nanostructures.
Furthermore, Fourier-transform spectroscopic holography is developed to achieve rapid, wavelength-resolved imaging, extending the approach toward spectroscopic microscopy. Together, these developments establish EUV multi-wavelength ptychography as a versatile tool for non-destructive, quantitative nanoscale metrology. The results contribute to advancing compact, laboratory-scale imaging systems with potential applications in semiconductor inspection, materials characterization, and nanoscience.
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