Particles in quantum vortex states (QVSs) carrying definite orbital angular momenta (OAM) bring different perspectives various fundamental interaction processes. When unique properties arise the QVS, understanding how OAM manifests itself between initial particles and outcome particle collisions becomes essential. This is made possible by applying complete description for all involved such that...

Electron-positron pair production via real and virtual photons is signi cant to the design of linear colliders, especially in the deep quantum regime (i.e., beamstrahlung parameter >> 1). In this regime, pair production via a virtual photon (the trident process) can become comparable in rate to pair production via a real beamstrahlung photon. We derive characteristics of the e+epairs produced v...

We examine the creation of electron-positron pairs in a very strong force field. Using numerical solutions to quantum field theory we calculate the spatial and momentum probability distributions for the created particles. A comparison with classical mechanical phase space calculations suggests that despite the fully relativistic and quantum mechanical nature of the matter creation process, most...

Using a quantum kinetic equation we study the possibility that focused beams at proposed x-ray free electron laser facilities can initiate spontaneous electron-positron pair production from the QED vacuum. Under conditions reckoned achievable at planned facilities, repeated cycles of particle creation and annihilation will take place in tune with the laser frequency. The peak particle number de...

Waves in pair plasmas have a fundamentally different dispersion due to the equal charge-to-mass ratios between negative and positive charges. In view of possible applications e.g. to electron-positron and fullerene pair plasmas, it is shown that there are no stationary large amplitude nonlinear structures in symmetric unmagnetized pair plasmas.