  The electron momentum density obtained from the Schwinger-like mechanism is
evaluated for a graphene sample immersed in a homogeneous time-dependent
electric field. Based on the analogy between graphene low-energy electrons and
quantum electrodynamics (QED), numerical techniques borrowed from strong field
QED are employed and compared to approximate analytical approaches. It is
demonstrated that for some range of experimentally accessible parameters, the
pair production proceeds by sequences of adiabatic evolutions followed by
non-adiabatic Landau-Zener transitions, reminiscent of the Kibble-Zurek
mechanism describing topological defect density in second order phase
transitions. For some field configurations, this yields interference patterns
in momentum space which are explained in terms of the adiabatic-impulse model
and the Landau-Zener-St\"{u}ckelberg interferometry.

Mesoscale and Nanoscale Physics;Quantum Physics