Related papers: Vacuum space charge effect in laser-based solid-st…
Ultrafast electron beams are essential for many applications, yet space-charge interactions in high-intensity beams lead to energy dissipation, coherence loss, and pulse broadening. Existing techniques mitigate these effects by using…
We report with single particle simulations that longitudinal chromatism, a commonly occuring spatio-temporal coupling in ultrashort laser pulses, can have a significant influence in the longitudinal acceleration of electrons via high-power,…
We show that under appropriate conditions the impact of a very short and intense laser pulse onto a plasma causes the expulsion of surface electrons with high energy in the direction opposite to the one of propagation of the pulse. This is…
Irradiation of sharp silver tips with femtosecond laser pulses leads to photoassisted coherent field emission without a static field. We reconstruct the time profile of the emission, and show that the process is entirely governed by the…
The screening of a test charge by partially degenerate non-ideal free electrons at conditions related to warm dense matter and dense plasmas is investigated using linear response theory and the local field correction based on ab inito…
We study spatial correlations in the ground state of a one-dimensional electron gas coupled to a dynamic quantum impurity. The system displays a non-trivial many-body effect known as the Fermi edge singularity: transitions between discrete…
We present an experimental investigation of band-gap shrinkage in n-type GaN using photoluminescence spectroscopy, as a function of electron concentration and temperature. The observed systematic shift of the band-to-band transition energy…
It is commonly agreed that the electromagnetic vacuum is not empty but filled with virtual photons. This leads to effects like Lamb shift and spontaneous emission. Here we argue that if the vacuum has virtual photons it might mean that it…
The strong light-field effect of (TMTTF)2AsF6 was investigated utilizing 1.5-cycle, 7-fs infrared pulses. The ultarfast (20 fs) and large (40%) response of the plasma-like reflectivity edge (0.7 eV) was analyzed by the changes in…
In this work, we present the implementation of all-optical method for directly measuring electron pulse duration in an ultrafast scanning electron microscope. Our approach is based on the interaction of electrons with the ponderomotive…
We report on charge state measurements of laser-accelerated carbon ions in the energy range of several MeV penetrating a dense partially ionized plasma. The plasma was generated by irradiation of a foam target with laser-induced hohlraum…
Proton beams with up to 100 pC bunch charge, 0.48 MeV cut-off energy and divergence as low as a $3^{\circ}$ were generated from solid targets at kHz repetition rate by a few-mJ femtosecond laser under controlled plasma conditions. The beam…
We report an experimental demonstration of single-photon switching in laser-cooled $^{87}$Rb atoms. A resonant probe pulse with an energy per unit area of one photon per $\lambda^2/2\pi$ propagates through the optically thick atoms. Its…
Previous theoretical studies have shown that attosecond electron dynamics can, in principle, be captured in electron momentum spectroscopy (EMS) using ultrashort electron pulses. By including further analytical considerations on the…
The effect of laser focusing conditions on the evolution of relativistic plasma waves in laser wakefield accelerators is studied both experimentally and with particle-in-cell simulations. For short focal length ($w_0 < \lambda_p$)…
Angle-resolved photoemission spectra of alkali metals exhibit a puzzling, non-dispersing peak in the apparent density of states near the Fermi energy. We argue that the holes left behind a significant fraction of photoejected electrons are…
We propose and analyze in detail a method to measure the in-air spatial spread parameter of clinical electron beams. Measurements are performed at the center of the beam and below the adjustable collimators sited in asymmetrical…
We investigated the possibility of using a layer of quantum dots (QDs) deposited on the microparticle surface for the measurement of the charge the microparticle acquires when immersed into a plasma. To that end, we performed the…
According to quantum electrodynamics (QED), a strong external field can make the vacuum state decay producing electron-positron pairs. Here we investigate emission of soft photons which accompanies a nonperturbative process of pair…
Recent results from our on going experimental investigation of the influence of space dependant electric fields on the weight of test particles are reported. Test particles were gold coated metal spheres of same size but of different…