  The Schwinger process in strong electric fields creates particles and
antiparticles that are entangled. The entropy of entanglement between particles
and antiparticles has been found to be equal to the statistical Gibbs entropy
of the produced system. Here we study the effect of quantum interference in
sequences of electric pulses, and show that quantum interference suppresses the
entanglement entropy of the created quantum state. This is potentially relevant
to quantum-enhanced classical communications. Our results can be extended to a
wide variety of two-level quantum systems.
