  In this paper, we report on the controllable negative differential resistance
(NDR) in a proposed planar graphene superlattice structure. High value of peak
to valley ratio (PVR) is predicted. This is significant because of appearance
of NDR with high PVR at low biases. Our finding is important since beside the
other potential applications of the graphene, proposes implementation of the
graphene based superlattice in electronic devices such as resonant tunneling
diode and filters.
