Conveners
General Talk 2
- Chair: Laura Corner
General Talk 2
- Chair: Matteo Tamburini
General Talk 2
- Chair: Patrick Copinger
Quantum electrodynamics (QED) cascades describe the exponential growth of an electron-positron-photon plasma in an intense electromagnetic (EM) field. Exponential growth is only possible if both electric and magnetic fields are present. In a nutshell, the electric field allows for every new generation of leptons to be re-accelerated after their creation. In contrast, the magnetic field plays a...
Plasmas immersed in ultra-intense electromagnetic fields radiate through QED channels high-energy photons which can decay into pairs. These pairs, if created in sufficient amounts, can significantly impact the background field. This is especially true in the context of QED avalanches created by intense lasers, where the exponentially growing density will eventually reach a critical value...
The quantum electrodynamic (QED) theory predicts the photon emission and pair creation in QED cascades mainly occur in a forward cone with finite angular spread $\Delta\theta \sim 1/\gamma_{i}$ along the momenta of incoming particles. This finite beaming effect has been assumed to be negligible because of the particles' ultra-relativistic Lorentz factor $\gamma_{i}\gg1$ in laser-driven QED...
Since the initial prediction of the onset of selfsustained QED cascades upon injection of particles in certain electromagnetic field configurations [1], the pivotal theory questions remain the same: (i) What are the general conditions required to trigger such cascades? (ii) How many electron-positron pairs can be produced? (iii) What is the threshold of the phenomenon, particularly in the...
I discuss high-harmonic generation from the vacuum in strong-field QED. Using the semi-classical approximation, I explicitly calculate the number of photons and the resulting harmonic spectrum in the presence of a spatially uniform linearly-polarized AC electric field, at the leading order in the fine-structure constant $\alpha$. I briefly compare the obtained results with the previous ones,...
