Monolayer graphene with an energy gap presents a pseudospin symmetry-broken ferromagnet with a perpendicular pseudomagnetization whose direction is switched by altering the type of doping between $n$ and $p$. We demonstrate an electrical current switching effect in the pseudospin version of a spin valve in which two pseudoferromagnetic regions are contacted through a normal graphene region. The proposed structure exhibits a pseudomagnetoresistance, defined as the relative difference of resistances of parallel and antiparallel alignments of the pseudomagnetizations, which can be tuned to unity. This perfect pseudomagnetic switching is found to show a strong robustness with respect to increasing the contact length, the effect of which we explain in terms of an unusually long-range penetration of an equilibrium pseudospin polarization into the normal region by proximity to a pseudoferromagnet. Our results reveal the potential of gapped graphene for realization of pseudospin-based nanoelectronics.

• Received 10 November 2010

DOI:https://doi.org/10.1103/PhysRevB.83.115422