Giulia Fulvia Mancini
Ptychographic Coherent Diffractive Imaging (CDI) [1,2] has revolutionized microscopy of nanomaterials and biological matter over the past decades [3]. By allowing to reconstruct simultaneously phase and amplitude of both the sample and of the imageforming beam, this powerful approach recently allowed to characterize and correct aberrations in beams beam carrying orbital angular momentum [4,5], crucially underpinning their practical use in chirality detection through helical dichroism [6]. Its combination with EUV compact light sources from High-Harmonic Generation (HHG) marked the advent of tabletop quantitative microscopy [7] in the ultrafast domain [8], enabling unprecedented capabilities of non-destructive nanometrology [9] and biological imaging [10]. These powerful demonstrations raised growing interest towards building new compact
implementations and to upgrade pre-existing HHG-based facilities towards microscopy. In this talk, I will address the required trade-off among Nyquist sampling, illumination function properties, and achievable resolutions, while retaining high throughput and data processing. I shall analyze the effects of misalignments on the obtained illumination functions, while accounting for the EUV optics surface errors and roughness, which is especially relevant for illumination functions, either structured or carrying orbital angular momentum, for their practical utilization. Our findings underpin the realization of real-time hyperspectral and ultrafast ptychographic imaging, fostering unprecedented understanding of functionality at the nanoscale, vital to next generation devices.
References
[1] D. Sayre, “Some implications of a theorem due to Shannon”, Acta Crystallographica, 5, 843–843 (1952).
[2] J. R. Fienup, "Reconstruction of an object from the modulus of its Fourier transform", Optics Letters, 3, 27-29 (1978).
[3] J. M. Rodenburg, "Ptychography and related diffractive imaging methods", Advances in Imaging and Electron Physics, 150, 87-184
(2008).
[4] L. Loetgering et al., "Advances in laboratory-scale ptychography using high harmonic sources", Optics Express, 30, 4133-4164 (2022).
[5] M. Pancaldi et al., "High-resolution ptychographic imaging at a seeded free-electron laser source using OAM beams", Optica, 11, 403-
411 (2024).
[6] J. R. Rouxel et al., "High-resolution ultrafast ptychographic imaging", Nature Photonics, 16, 570–574 (2022).
[7] D. Gardner et al., "Subwavelength coherent imaging of periodic samples using a 13.5 nm tabletop high-harmonic light source", Nature
Photonics, 11, 259–263 (2017).
[8] R. M. Karl Jr. et al., "Full-field imaging of thermal and acoustic dynamics in an individual nanostructure using tabletop high harmonic
beams", Science Advances, 4, eaau4295 (2018).
[9] E. R. Shanblatt et al., "Quantitative chemically specific coherent diffractive imaging of reactions at buried interfaces with few nanometer
precision", Nano Letters, 16, 5444−5450 (2016).
[10] S. Jiang et al., "Spatial- and Fourier-domain ptychography for high-throughput bio-imaging", Nature Protocols, 18, 2051–2083 (2023).