High-voltage laboratory experiments show that discharges in air, generated over a gap of one meter with maximal voltage of 1 MV, may produce X-rays with photon energies up to 1 MeV. It has been suggested that the photons are bremsstrahlung from electrons accelerated by the impulsive, enhanced field during collisions of negative and a positive streamers. To explore this process, we have conducte...

A deterministic photon-photon quantum logic gate is a long-standing goal. Building such a gate becomes possible if a light pulse containing only one photon imprints a phase shift of π onto another light field. We experimentally demonstrate the generation of such a π phase shift with a single-photon pulse. A first light pulse containing less than one photon on average is stored in an atomic gas....

In the near future, laser-plasma particle accelerators will be able to sustain electric fields in excess of 100 GeV/m, along plasma channels several Rayleigh lengths long. For these extreme conditions, present day laser wakefield diagnostics such as Frequency Domain Interferometry will not be able to resolve the wake field structure and determine the magnitude of the electric field. In this pap...

A bstract In this paper we present an algorithm to add photon-splitting corrections the Yennie-Frautschi-Suura-style soft-photon resummation available in S herpa MonteCarlo event generator. Photon-splitting enter at NNLO QED and, as these effects are not incorporated standard FSR resummations, their size is larger than pure hard photon-emission same order. We introduce different lepton dressing...