Graphene p-n junction arrays as quantum-Hall resistance standards

摘要

We demonstrate a device concept to fabricate resistance standards made ofquantum Hall series arrays by using p-type and n-type graphene. The ambipolarnature of graphene allows fabricating series quantum Hall resistors withoutcomplex multi-layer metal interconnect technology, which is required when usingconventional GaAs two-dimensional electron systems. As a prerequisite for aprecise resistance standard we confirm the vanishing of longitudinal resistanceacross a p-n junction for metrological relevant current levels in the range ofa few muA.