Trident pair production in plane waves: Coherence, exchange, and spacetime inhomogeneity

Understand

We study the trident process in inhomogeneous plane wave background fields.

• We obtain compact analytical expressions for all terms in the probability, including the exchange part, for an arbitrarily shaped plane wave.
• We evaluate the probability numerically using complex deformation of lightfront time integrals and derive various analytical approximations.
• Our results provide insights into the importance of the one-step and exchange parts of the probability relative to the two-step process, and into the convergence to the locally constant field approximation.