(The) electronic transport properties of high bias voltage exposed graphene devices

Abstract

Graphene nanostructure shows various intriguing quantum transport properties. Through reducing graphene width can make the quantum confinement energy gap which leads to overcome the gapless nature of gra-phene. Application of high bias voltage exposure resulted in the nanoconstriction of a graphene device. Each device showed different electronic transport properties. We fabricated graphene devices and performed the bias voltage exposure process at low temperature in a cryostat. Non-suspended graphene devices showed a peculiar feature in current annealing stage. And also suspended graphene devices showed a different feature in current annealing stage. We achieved high mobility only in suspended graphene devices. After the initial stage of current annealing, the conductance of the devices suppressed and showed quantum transport properties. And a sufficient iterations of the high bias voltage exposure processes showed a large I(V) gap behavior. The transformation of the electronic transport properties along with high bias voltage exposure processes can be attributed to the reduction of the graphene width. During the high bias voltage exposure process, we controlled the bias voltage to ensure that the constriction processed sufficiently slowly. The resistance change rate is strictly controlled with a positive and/or negative feedback loop. With this method, we found very intriguing the evolution of various quantum phases in a disordered graphene device.