A5024730657- Laser-Matter Interactions and Applications
- Advanced Chemical Physics Studies
- Laser-Plasma Interactions and Diagnostics
- Mass Spectrometry Techniques and Applications
- Advanced Fiber Laser Technologies
- Advanced X-ray Imaging Techniques
- Advanced Electron Microscopy Techniques and Applications
- Spectroscopy and Quantum Chemical Studies
- Atomic and Molecular Physics
- Ion-surface interactions and analysis
- X-ray Spectroscopy and Fluorescence Analysis
- Terahertz technology and applications
- Spectroscopy and Laser Applications
- Biosensors and Analytical Detection
- Advanced Biosensing Techniques and Applications
- Gold and Silver Nanoparticles Synthesis and Applications
- Gyrotron and Vacuum Electronics Research
- Particle Accelerators and Free-Electron Lasers
ETH Zurich
2017-2021
Universität Hamburg
2012-2019
Center for Free-Electron Laser Science
2012-2019
Friedrich Schiller University Jena
2012
Attosecond metrology has so far largely remained limited to titanium:sapphire lasers combined with an active stabilization of the carrier-envelope phase (CEP).These sources limit achievable photon energy ∼100 eV which is too low access X-ray absorption edges most second-and third-row elements are central chemistry, biology and material science.Therefore, intense efforts underway extend attosecond soft-X-ray (SXR) domain using mid-infrared (mid-IR) drivers.Here, we introduce experimentally...
High-harmonic generation (HHG) in gases has been the main enabling technology of attosecond science since its discovery. Recently, HHG from solids demonstrated, opening a lively area research. In contrast, harmonic liquids so far remained restricted to low harmonics visible regime. Here, we report observation and detailed characterization extreme ultraviolet liquid water several alcohols extending beyond 20 eV. This advance was enabled by implementation recent flat-microjet technology, which...
We report the first experimental observation of terahertz (THz) radiation from rear surface a solid target while interacting with an intense laser pulse. Experimental and two-dimensional particle-in-cell simulations show that observed THz is mostly emitted at large angles to normal. Numerical results point out part emission originates micron-scale plasma sheath target, which also responsible for ion acceleration. This opens perspective application detection on-site diagnostics particle...
We report on the experimental observation of a strong-field dressing an autoionizing two-electron state in helium with intense extreme-ultraviolet laser pulses from free-electron laser. The asymmetric Fano line shape this transition is spectrally resolved, and we observe modifications resonance asymmetry structure for increasing free-electron-laser pulse energy order few tens Microjoules. A quantum-mechanical calculation time-dependent dipole response state, driven by classical (XUV)...
Auger decay carries valuable information about the electronic structure and dynamics of atoms, molecules, solids. Here we furnish evidence that under certain conditions electrons are subject to an energetic chirp. The effect is disclosed in time-resolved streaking experiments on Xe NOO Kr MNN using extreme-ultraviolet pulses from free-electron laser Hamburg as well a high-order harmonic source. origin this found be exchange energy between electron earlier emitted correlated photoelectron....
We demonstrate time-resolved nonlinear extreme-ultraviolet absorption spectroscopy on multiply charged ions, here applied to the doubly neon ion, driven by a phase-locked sequence of two intense free-electron laser pulses. Absorption signatures resonance lines due $2p--3d$ bound--bound transitions between spin-orbit multiplets ${^{3}P}_{0,1,2}$ and ${^{3}D}_{1,2,3}$ transiently produced ${\mathrm{Ne}}^{2+}$ ion are revealed, with time-dependent spectral changes over time-delay range...
Abstract High-intensity ultrashort pulses at extreme ultraviolet (XUV) and x-ray photon energies, delivered by state-of-the-art free-electron lasers (FELs), are revolutionizing the field of ultrafast spectroscopy. For crossing next frontiers research, precise, reliable practical photonic tools for spectro-temporal characterization becoming steadily more important. Here, we experimentally demonstrate a technique direct measurement frequency chirp extreme-ultraviolet laser based on fundamental...
Experiments selectively excite and probe specific core electrons in CH${}_{2}$I${}_{2}$ to follow the molecule's internal dynamics also pave way toward site-selective control of chemical reactions.
Attosecond photoemission delays for all the valence (5p3/2, 5p1/2, 5s, 4d5/2, 4d3/2) subshells of xenon have been accessed using interferometric RABBITT technique. The 4d subshell in Xe first time, to best our knowledge, due high photon energy used. A novel technique single-shot referencing collinear back-focusing geometry has introduced. This enables us distinguish signal from principal photoelectron peaks ionization by extreme ultraviolet radiation only and infrared-induced sideband...
Attosecond streaking is a powerful tool to investigate ultrafast electron dynamics on the attosecond time scale. To obtain highest temporal resolution in pump-probe experiment, soft-X-ray (SXR) and infrared (IR) pulses have be carefully characterized. Here, we present detailed description of our recent generalization Volkov-transform generalized projection algorithm (VTGPA) its application multiple overlapping photoelectron bands. This method allows for complete reconstruction both IR SXR...
Ultrafast dynamics of a molecular wave packet created by strong 120-fs near-infrared (800 nm) laser pulse in iodine has been probed synchronized 13.4-nm, 35-fs extreme-ultraviolet pulses delivered the free-electron facility Hamburg, FLASH. The kinetic energy release multiply charged ionic fragments reveals three essential steps strong-field-induced fragmentation dynamics: (i) creation I${}_{2}$${}^{2+}$ and (I${}_{2}$${}^{2+}$)${}^{*}$ ions proceeds within (75 $\ifmmode\pm\else\textpm\fi{}$...
A compact time-of-flight spectrometer for applications in attosecond spectroscopy the liquid and gas phases is presented. It allows altering collection efficiency by transitioning between field-free magnetic-bottle operation modes. High energy resolution (ΔE/E = 0.03 kinetic energies >20 eV) achieved despite short flight-tube length through a homogeneous deceleration potential at beginning of flight tube. closing mechanism isolating vacuum system tube from interaction region order to...
An annular infrared (IR) laser beam has been used for high-order harmonic generation reaching a cut-off energy of 90 eV extreme-ultraviolet–infrared (XUV-IR) pump-probe experiments in an intrinsically stable attosecond beamline. The harmonics along the axis missing portion decreases IR power load on thin metallic foils that are removing residual and shaping XUV pulses from high-harmonic generation. This finds applications high-average-power few-cycle systems, where high-average destroys...
We present and demonstrate an experimental scheme that enables overlap-free reconstruction of attosecond beating by interference two-photon transitions (RABBITT) measurements at high extreme-ultraviolet (XUV) photon energies. A compact passively-stabilized beamline employing a multilayer (ML) mirror allows us to obtain XUV pulses consisting only two odd high-harmonic orders from pulse train (APT). compare our new technique existing schemes are used perform RABBITT discuss how resolves the...
Directional breaking of the C-H/C-D molecular bond is manipulated in acetylene (C2H2) and deuterated (C2D2) by waveform controlled few-cycle mid-infrared laser pulses with a central wavelength around 1.6 μm at an intensity about 8 × 1013 W/cm2. The directionality deprotonation changing carrier-envelope phase (CEP). CEP-control can be attributed to laser-induced superposition vibrational modes, which sensitive sub-cycle evolution waveform. Our experiments simulations indicate that...
Soft-x-ray free-electron-laser pulses were used to create highly charged molecular tetrabromothiophene species by sequential multiphoton ionization from bromine $3d$ orbitals. The experiment was performed at the SACLA facility in Japan and products of dissociation analyzed means multicoincidence momentum-resolved ion time-of-flight spectroscopy. Total charge states up +13 atomic units produced, creating a particular pattern for carbon ions, Coulomb implosion, due concerted forces surrounding...
A setup for an all-XUV transient absorption spectroscopy at free-electron lasers, was developed and employed to explore XUV-excited dynamics XUV-driven nonlinear phenomena.
Momenta of ions from diiodomethane molecules after multiple ionization by soft-X-ray free-electron-laser pulses are measured. Correlations between the ion momenta extracted covariance methods formulated for use in multiparticle momentum-resolved time-of-flight spectroscopy. Femtosecond dynamics dissociating multiply charged cations is discussed and interpreted using simulations based on a classical Coulomb explosion model including charge evolution.
Using electron spectroscopy, we investigated the nanoplasma formation process generated in xenon clusters by intense soft x-ray free laser (FEL) pulses. We found clear FEL intensity dependence of spectra. Multistep ionization and subsequent frustration features are evident for low FEL-intensity region, thermal emission emerges at high intensity. The present spectra is well addressed parameter introduced Arbeiter Fennel [New J. Phys. 13, 053022 (2011)].
The carrier envelop phase (CEP) of isolated attosecond pulses (IAPs) is theoretically and experimentally investigated based on the assumption that a significant contribution originates from measurable CEP jitter driving laser. By solving timedependent Schr\"odinger equation, it demonstrated IAPs minimized when pulse near its Fourier limit but with slightly negative chirp. Although, at present utilization has limited applications, understanding characterization first step towards exact...
We have investigated the Auger decay in temporal domain by applying a terahertz streaking light field. Xenon and krypton atoms were studied implementing free-electron laser Hamburg (FLASH) as well source of high-order harmonic radiation combined with pulses from an optical rectification source. The observed linewidth asymmetries streaked spectra suggest chirped electron emission which is understood terms field-assisted post-collision interaction. experimentally obtained results agree model...
In this article we present a new diagnostic approach utilizing flow-cytometry to study compounds of nanoparticle samples in solution by analysis their scattering patterns retrieved from the cytometric measurements. As specific enhancement technique as well pattern nanoparticles fluorescent (529 nm). A significant cytometry measurements is observed supporting an improved separation particle formations that are clearly resolved cytograms. The experiment prepared 80 nm citrate-capped gold...
Summary form only given. Attosecond metrology has so far remained limited to Ti:Sa lasers combined with an active stabilization of the carrier-envelope phase (CEP), where achievable photon energy is ~100eV. This too low access X-ray absorption edges most second- and third-row elements which are central chemistry, biology material science. The quadratic scaling ponderomotive wavelength enables generate energies in soft-X-ray (SXR) domain mid-IR laser sources. We use our commercial TiSa system...
Summary form only given. Attosecond-streaking spectroscopy [1], has given real-time access to photoionization delays of atoms in the gas phase [2], and additional effects electron transport processes through atomic layers interfaces solid-state systems [3, 4]. Here, we report on first attosecond-streaking experiments liquid samples. We have realized photoelectron water phases using a microjet [5].
Minimizing the CEP jitter of isolated attosecond pulses (IAP) will be important for future applications. This is experimentally and theoretically investigated can minimized when driving pulse near its Fourier limit but with slightly negative chirp. Thus, understanding characterization IAPs a first step towards exact control electric field IAP pulses.