Graphene/Metal Contacts: Bistable States and Novel Memory Devices

Graphene field-effect transistors (GFETs) with different metal electrodes are fabricated to explore the contact characteristics. The contact resistance and the spatial potential distribution along the graphene/metal interface are investigated. The low-doped graphene/metal contact can be reversibly switched between "ohmic" and "space-charge region limited" states. The observed switching attributes are highly reproducible and stable, which provides a new avenue to produce high-performance graphene memory devices.