Ballistic conductivity of graphene channel with p-n junction on ferroelectric domain wall

Abstract

We study the impact of the ferroelectric domain wall on the ballistic conductance of the single-layer graphene channel in the heterostructure graphene / physical gap / ferroelectric film using Wentzel-Kramers-Brillouin approximation. Both self-consistent numerical modeling of the electric field and space charge dynamics in the heterostructure and approximate analytical theory show that the domain wall contact with the surface creates p-n junction in graphene channel. We calculated that the carriers' concentration induced in graphene by uncompensated ferroelectric dipoles originated from the spontaneous polarization abrupt near the surface can reach the values of 1019 m-2 order, which is in two orders higher than it can be obtained for the gate doped graphene on non-ferroelectric substrates. Therefore we predict that graphene channel with the p-n junction caused by ferroelectric domain wall would be characterized by rather high ballistic conductivity.