Electric field effects in graphene-complex-oxide heterostructures

Graphene has excellent electrical, chemical, and mechanical properties, which makes it a promising material for developing nanoscale electronic devices, while complex-oxide heterostructure provide sharply confined multifunctional interfaces that can be tailored at nanoscale dimensions. The combination--graphene-complex oxide heterostructures--merge the multifunctional properties of oxide interfaces such as high dielectric constant, metal-insulator-transition, magnetism, and superconductivity, with the unique electronic properties of graphene. Here we demonstrate some simple three-terminal field-effect devices that combine the electronic properties of these two systems. Nanoscale devices are fabricated from graphene/LaAlO$_3$/SrTiO$_3$ heterostructures using c-AFM lithography. We demonstrate field effects in both the graphene and LaAlO$_3$/SrTiO$_3$ interface. These novel heterostructures open new avenues for creating devices that combine the most interesting and unique properties of the coupled two-dimensional electron system.