  We show that a moderately strong constant electric field in the plane of a
monolayer graphene sheet can create particle-hole pairs at an observable rate.
The pairs undergo zitterbewegung in opposite directions leading to a Hall-like
separation of the charge carriers and a measurable transverse dipole moment is
predicted which serves as the signature of the zitterbewegung. In contrast with
the created pairs, the zero modes of the excitation induce a current transverse
to the electric field but do not result in separated charges. For bilayer
graphene a similar effect by the electric field is shown not to be possible.
