Coulomb Blockade and Hopping Conduction in Graphene Quantum Dots Array

摘要

We show that the low temperature electron transport properties of chemicallyfunctionalized graphene can be explained as sequential tunneling of chargesthrough a two dimensional array of graphene quantum dots (GQD). Below 15 K, atotal suppression of current due to Coulomb blockade through GQD array wasobserved. Temperature dependent current-gate voltage characteristics showCoulomb oscillations with energy scales of 6.2-10 meV corresponding to GQDsizes of 5-8 nm while resistance data exhibit an Efros-Shklovskii variablerange hopping arising from structural and size induced disorder.