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Probing electron correlation on the attosecond time scale
We present experimental measurements and theoretical calculations of single and double ionization time delays in various noble gases using an interferometric method. The measured delays allow us to extract information on the electron correlation.
Confinement of attosecond train pulses by using a modulated polarization IR pulse
We study the temporal and spectral behaviour of high order harmonics generated by pulses with temporally modulated polarization. We observe a harmonic temporal confinement and a harmonic spectral broadening, compatible with 1 -or-2 attosecond pulse emission.
Femtosecond pump-probe photoelectron spectroscopy of predissociative Rydberg states in acetylene
We employ a pump-probe approach to molecular photoionization to study fast dissociation of Rydberg states in acetylene. By using time-resolved photoelectron spectroscopy to study the electronic state of the resulting ions we are able to monitor the system continuously during dissociation or rearrangement. We find that the predissociative lifetime for the 3R‴ (v′2 = 1) Rydberg state is about 150 fs
High repetition rate XUV laser source based on OPCPA for photoemission electron microscopy applications
We present a 200 kHz XUV source driven by an optical parametric chirped pulse amplification system. The advantage for photoemission electron microscopy of this high-repetition rate will be discussed.
Stabilized interferometric attosecond timing measurements
We perform interferometric attosecond timing measurements to study XUV photoionization in noble gases, to diagnose macroscopic phase-matching conditions in high-order harmonic generation, and to investigate single-photon double-ionization by detecting electron pairs in coincidence.
Coherence properties of high-order harmonics : Application to high-density laser-plasma diagnostic
We present two interferometry schemes in the extreme ultraviolet, based on either the wave-front division of a unique harmonic beam (1st scheme) or two spatially separated, phase-locked harmonic sources (2nd scheme). In the first scheme using a Fresnel bimirror interferometer, we measure the degree of spatial coherence of the 13 th harmonic generated in xenon, as a function of different parameters
The ELI ALPS research infrastructure : Scaling Attosecond Pulse Generation for a large scale infrastructure
Along with the review of the technological frame that will be available at the Extreme Light Infrastructure Attosecond Light Pulse Source (ELI-ALPS) we present considerations applicable to large-scale attosecond sources driven by high-power laser pulses.
Power-scaling attosecond sources using universal scaling principles for nonlinear optical processes in gases
Scaling attosecond sources to higher pulse energy and/or repetition rate can benefit many applications. We present a scaling framework for nonlinear light-matter interactions, applicable to attosecond pulse generation and other nonlinear phenomena as e.g. filamentation.
Photoionization time delay measurement close to a fano resonance using tunable attosecond pulses
We investigate the influence of a Fano resonance on the delays for electron emission in two-photon, near-resonant ionization of argon. The delays were measured using an interferometric method that employed an attosecond pulse train.
Compact, high-repetition-rate OPCPA system for high harmonic generation
A compact, high-repetition rate optical parametric chirped pulse amplifier system emitting CEP-stable, few-cycle pulses with 10 μJ of pulse energy is reported for the purpose of high-order harmonic generation. The system is seeded from a commercially available, CEP-stabilized Ti:sapphire oscillator, delivering an octave-spanning spectrum from 600-1200 nm. The oscillator output serves on the one ha
Atomic physics with attosecond pulses
No title
Progress in attosecond technology-application to momentum shearing interferometry of electron wavepackets
The recently demonstrated momentum shearing interferometry technique, aimed at recovering phase information about electronic wave packets (EWP) will be presented. Possibilities to improve this technique will be discussed.
Characterization of attosecond pulse trains
Ultrashort light pulses, as short as 100 as, can be produced from high harmonic generation (HHG) in an atomic gas medium. This major achievement of the last 6 years in high field physics has now been demonstrated in different conditions of medium-field interaction [1].
Control of the frequency chirp rate of high harmonic pulses
We measured the frequency chirp rate of harmonics 13 to 23 in argon by cross-correlation with a short femtosecond probe pulse. We directly measured the negative chirp due to the atomic dipole phase and demonstrated that an additional chirp on the pump pulse was transferred to the qth harmonic as q times the fundamental chirp.
Attosecond control of electron localization in one- and two-color dissociative ionization of H2 and D2
We present one-color (IR) and two-color (single attosecond XUV pulse + IR) experiments where the sub-cycle evolution of the electric field of light is used to control the dissociative ionization of hydrogen and deuterium molecules.
Controlling the duration of XUV high order harmonic pulses
We modulate temporally the polarization of a ∼ 30 fs, 800 nm IR pulse and use it to generate high order harmonics. The harmonic emission can clearly be confined and the XUV pulse duration can be continuously tuned from - 5 - 7 fs to 50 fs.
Attosecond excitation of electron wavepackets
We present experiments, supported by time-dependent Schrödinger simulations, on the dynamics of Helium bound states after an attosecond excitation in the presence of a strong infrared laser field.
The ELI-ALPS secondary sources : A getaway to scientific excellence
The essence of ELI-ALPS, the laser driven secondary sources ranging from X-ray and X-UV to THz with duration as short as tens of attoseconds, are designed to be available for users from 2016.