Magnetocapacitance and dissipation factor of epitaxial graphene Hall bars

We report measurements of the magneto-capacitance and the associated dissipation factor of graphene-based quantum Hall effect devices at frequencies in the kHz range. The main motivation for this work is yielding information for the modeling and optimization of quantum Hall resistance devices measured with alternating current, but here we focus on the characteristic ac properties of graphene and the relevant loss mechanism.