180 citations · 939 across the 22 of their papers we have counts for
23 papers
Unleashing HHG Efficiency: The Role of Driving Pulse Duration
Robert Klas, Martin Gebhardt, Jan Rothhardt +1
High harmonic generation (HHG) is a crucial technology for compact, high-brightness extreme ultraviolet (XUV) and soft X-ray sources, which are key to advancing both fundamental an…
Laser-driven high-flux source of coherent quasi-monochromatic extreme ultraviolet radiation for coincidence spectroscopy
Julian Späthe, Sebastian Hell, Martin Wünsche +6
We present a source of coherent extreme ultraviolet (XUV) radiation with a flux of 10 photons per second at 26.5 eV. The source is based on high-harmonic generation (HHG) in…
Coincidence measurement of two-photon double ionization of argon through an autoionizing resonance
Sebastian Hell, Julian Späthe, Morten Førre +8
We present coincidence measurements of two-photon double-ionization (TPDI) of argon driven by femtosecond pulses tunable around 26.5 eV photon energy, which are obtained from a hig…
Bayesian multi-exposure image fusion for robust high dynamic range ptychography
Shantanu Kodgirwar, Lars Loetgering, Chang Liu +6
The limited dynamic range of the detector can impede coherent diffractive imaging (CDI) schemes from achieving diffraction-limited resolution. To overcome this limitation, a straig…
Broadband ptychography using curved wavefront illumination
Daniel S. Penagos Molina, Lars Loetgering, Wilhelm Eschen +2
We examine the interplay between spectral bandwidth and illumination curvature in ptychography. By tailoring the divergence of the illumination, broader spectral bandwidths can be…
High-speed and wide-field nanoscale table-top ptychographic EUV imaging and beam characterization with a sCMOS detector
Wilhelm Eschen, Chang Liu, Daniel S. Penagos Molina +3
We present high-speed and wide-field EUV ptychography at 13.5 nm wavelength using a table-top high-order harmonic source. By employing a scientific complementary metal oxide semico…
PtyLab.m/py/jl: a cross-platform, open-source inverse modeling toolbox for conventional and Fourier ptychography
Lars Loetgering, Mengqi Du, Dirk Boonzajer Flaes +11
Conventional (CP) and Fourier (FP) ptychography have emerged as versatile quantitative phase imaging techniques. While the main application cases for each technique are different,…
Visualizing the ultra-structure of microorganisms using table-top extreme ultraviolet imaging
Chang Liu, Wilhelm Eschen, Lars Loetgering +10
Table-top extreme ultraviolet (EUV) microscopy offers unique opportunities for label-free investigation of biological samples. Here, we demonstrate ptychographic EUV imaging of two…
Material-specific high-resolution table-top extreme ultraviolet microscopy
Wilhelm Eschen, Lars Loetgering, Vittoria Schuster +9
Microscopy with extreme ultraviolet (EUV) radiation holds promise for high-resolution imaging with excellent material contrast, due to the short wavelength and numerous element-spe…
High-average-power femtosecond laser at 258 nm
Michael Müller, Arno Klenke, Thomas Gottschall +6
We present an ultrafast fiber laser system delivering 4.6 W average power at 258 nm based on two-stage fourth-harmonic generation in beta barium borate (BBO). The beam quality is c…
Energetic sub-2-cycle laser with 220 W average power
Steffen Hädrich, Marco Kienel, Michael Müller +12
Few-cycle lasers are essential for many research areas such as attosecond physics that promises to address fundamental questions in science and technology. Therefore, further advan…
Real-time phase-retrieval and wavefront sensing enabled by an artificial neural network
Jonathon White, Sici Wang, Wilhelm Eschen +1
In this manuscript we demonstrate a method to reconstruct the wavefront of focused beams from a measured diffraction pattern behind a diffracting mask in real-time. The phase probl…
Agile spectral tuning of high order harmonics by inteference of two driving pulses
Vittoria Schuster, Vinzenz Hilbert, Robert Klas +2
In this work the experimental realization of a tunable high photon flux extreme ultraviolet light source is presented. This is enabled by high harmonic generation of two temporally…
Ultra-short-pulse high-average-power Megahertz-repetition-rate coherent extreme-ultraviolet light source
R. Klas, A. Kirsche, M. Gebhardt +5
High harmonic generation (HHG) enables coherent extreme-ultraviolet (XUV) radiation with ultra-short pulse duration in a table-top setup. This has already enabled a plethora of app…
Broadband holography-assisted coherent imaging -- towards attosecond imaging at the nanoscale
Wilhelm Eschen, Sici Wang, Chang Liu +7
In recent years nanoscale coherent imaging has emerged as an indispensable imaging modality allowing to surpass the resolution limit given by classical imaging optics. At the same…
Ultraviolet Dual Comb Spectroscopy: A Roadmap
Vittoria Schuster, Chang Liu, Robert Klas +4
Dual Comb Spectroscopy proved its versatile capabilities in molecular fingerprinting in different spectral regions, but not yet in the ultraviolet (UV). Unlocking this spectral win…
High-precision calculations of the spin-allowed transition in C {\small III}
Moazzam Bilal, Andrey V Volotka, Randolf Beerwerth +3
Large-scale relativistic calculations are performed for the transition energy and line strength of the transition in Be-like…
Wavelength-scale ptychographic coherent diffractive imaging using a high-order harmonic source
Getnet K. Tadesse, Wilhelm Eschen, Robert Klas +9
Ptychography enables coherent diffractive imaging (CDI) of extended samples by raster scanning across the illuminating XUV/X-ray beam thereby generalizing the unique advantages of…
Table-Top Milliwatt-Class Extreme Ultraviolet High Harmonic Light Source
Robert Klas, Stefan Demmler, Maxim Tschernajew +5
Extreme ultraviolet (XUV) lasers are essential for the investigation of fundamental physics. Especially high repetition rate, high photon flux sources are of major interest for red…
High Speed and High Resolution Table-Top Nanoscale Imaging
G. K. Tadesse, R. Klas, S. Demmler +8
We present a table-top coherent diffraction imaging (CDI) experiment based on high-order harmonics generated at 18 nm by a high average power femtosecond fiber laser system. The hi…
High-repetition-rate and high-photon-flux 70 eV high-harmonic source for coincidence ion imaging of gas-phase molecules
Jan Rothhardt, Steffen Hädrich, Yariv Shamir +23
Unraveling and controlling chemical dynamics requires techniques to image structural changes of molecules with femtosecond temporal and picometer spatial resolution. Ultrashort-pul…
High photon flux table-top coherent extreme ultraviolet source
Steffen Hädrich, Arno Klenke, Jan Rothhardt +6
High harmonic generation (HHG) enables extreme ultraviolet radiation with table-top setups. Its exceptional properties, such as coherence and (sub)-femtosecond pulse durations, hav…
Enhancing narrowband high order harmonic generation by Fano resonances
Jan Rothhardt, Steffen Hädrich, Stefan Demmler +4
Resonances in the photo-absorption spectrum of the generating medium can modify the spectrum of high order harmonics. In particular, window-type Fano resonances can reduce photo-ab…