Speaker
Christian Kohlfürst
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P4.2009.pdf
Phase-space analysis of the Schwinger effect in inhomogeneous
electromagnetic fields
Christian Kohlfürst1,2
1 Helmholtz-Institute Jena, Fröbelstieg 3, 07743 Jena, Germany
2 Theoretisch-Physikalisches Institut, Abbe Center of Photonics,
Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, 07743 Jena, Germany
We have studied Schwinger pair production in spatially and temporally inhomogeneous high-
intensity few-cycle pulses [1, 2]
2 2 2t sin (ωt + φ ) − ωτ 2 cos (ωt + φ )
ε z t
E(t, z) = −∂t A(t, z) = exp − 2 − 2 × ex , (1)
ω λ τ τ2
2
t 2 2z sin (ωt + φ )
ε z
B(t, z) = ∇ × A(t, z) = − exp − 2 − 2 ey , (2)
ω λ τ λ2
where ε determines the electric field strength in units of m2 /e, τ sets the temporal scale and λ
specifies the spatial scale. The parameters ω and φ control the pulse structure.
Employing advanced numerical methods, we have been able to produce accurate numeri-
cal solutions of a quantum kinetic theory. We have computed particle (electrons and positrons)
momentum spectra, see Fig. 1, as well as spatial-momentum distribution functions in order
to thoroughly investigate how spatial and temporal variations in the electric and magnetic
fields affect the particle distribution n (z, px , pz ). Moreover, we have introduced a semi-classical
model on the basis of an effective theory for the particle production rate taking into account
instantaneous pair production and relativistic
single-particle dynamics.
We have found remarkable signatures of quan-
tum interferences and spin-field interactions. Addi-
tionally, we observed the formation of characteristic
patterns strongly depending on the carrier-envelope
phase of the background fields. Figure 1: Density plot of the particle dis-
References tribution function n (px , pz ) (quantum kinetic
[1] C. Kohlfürst and R. Alkofer, Phys. Lett. B 756 (2016) 371 calculation) in momentum space.
[2] C. Kohlfürst, arXiv:1708.08920 [quant-ph]
