Related papers: Tracing non-equilibrium plasma dynamics on the att…
We investigate the absorption line shapes of laser-dressed atoms beyond the single-atom response, by using extreme ultraviolet (XUV) attosecond pulse trains to probe an optically thick helium target under the influence of a strong infrared…
Attosecond pulses can be used to initiate and control electron dynamics on a sub-femtosecond time scale. The first step in this process occurs when an atom absorbs an ultraviolet photon leading to the formation of an attosecond electron…
We present an innovative beamline for extreme ultraviolet (XUV)-infrared (IR) pump-probe reflection spectroscopy in solids with attosecond temporal resolution. The setup uses an actively stabilized interferometer, where attosecond pulse…
Attosecond pulses in the soft-X-ray (SXR) to water-window energy region offer the tools for creating and studying target specific localized inner-shell electrons or holes in materials, enable monitoring or controlling charge and energy…
The harmonic emission from cluster nanoplasmas subject to short, intense infrared laser pulses is analyzed by means of particle-in-cell simulations. A pronounced resonant enhancement of the low-order harmonic yields is found when the Mie…
The motion of electrons and ions in medium-sized rare gas clusters (1000 atoms) exposed to intense laser pulses is studied microscopically by means of classical molecular dynamics using a hierarchical tree code. Pulse parameters for optimum…
The ability to perform attosecond-pump attosecond-probe spectroscopy (APAPS) is a longstanding goal in ultrafast science. While first pioneering experiments demonstrated the feasibility of APAPS, the low repetition rates (10-120 Hz) and the…
We combine different wavelengths from an intense high-order harmonics source with variable delay at the focus of a split-mirror interferometer to conduct pump-probe experiments on gas-phase molecules. We report measurements of the time…
The early stage density oscillations of the electronic charge in molecules irradiated by an attosecond XUV pulse takes place on femto- or subfemtosecond timescales. This ultrafast charge migration process is a central topic in attoscience…
Ultrafast laser excitation can create coherent superpositions of electronic states in molecules and trigger ultrafast flow of electron density on few- to sub-femtosecond time scales. While recent attosecond experiments have addressed…
Parametric amplification of attosecond coherent pulses around 100 eV at the single-atom level is demonstrated for the first time by using the 3D time-dependent Schr{\"o}dinger equation in high-harmonic generation processes from excited…
The interaction of high-intensity laser pulses and solid targets provides a promising way to create compact, tunable and bright XUV attosecond sources that can become a unique tool for a variety of applications. However, it is important to…
Clusters excited by intense laser pulses are a unique source of warm dense matter, that has been the subject of intensive experimental studies. The majority of those investigations concerns atomic clusters, whereas the evolution of…
This work theoretically investigates high-order harmonic generation in rare gas atoms driven by two temporally delayed ultrashort laser pulses. Apart from their temporal delay, the two pulses are identical. Using a single-atom model of the…
Sub-angstrom spatial resolution of electron density coupled with sub-femtosecond temporal resolution is required to directly observe the dynamics of the electronic structure of a molecule after photoinitiation or some other ultrafast…
Manipulation of intense pulse propagation in gas-filled capillaries is desirable for various high-field applications. Tuning the parameters of the driving laser pulse and the working gas is the conventional approach, and it provides limited…
The processing of energy by transfer and redistribution plays a key role in the evolution of dynamical systems. At the ultrasmall and ultrafast scale of nanosystems, quantum coherence could in principle also play a role and has been…
Context: Long-period intensity pulsations were recently detected in the EUV emission of coronal loops, and have been attributed to cycles of plasma evaporation and condensation driven by thermal non-equilibrium (TNE). Numerical simulations…
Tremendous advances in laser pump-probe techniques open the door for the observation in real time of ultrafast \textit{electronic} processes. Particularly attractive is the visualization of interatomic processes where one can follow the…
We examine the effect of cluster size on the interaction of Ar$_{55}$-Ar$_{2057}$ with intense extreme ultraviolet (XUV) pulses, using a model we developed earlier that includes ionization via collisional excitation as an intermediate step.…