Gates controlled parallel-coupled double quantum dot on both single layer and bilayer graphene

Abstract

We present quantum transport measurements of gates controlled parallel-coupled double quantum dot (PDQD) device on both bilayer and single layer graphenes. The interdot coupling strength can be effectively tuned from weak to strong by in-plane plunger gates. All the relevant energy scales and parameters can be extracted from the honeycomb charge stability diagrams. The present method of designing and fabricating graphene PDQD is demonstrated to be general and reliable and will enhance the realization of graphene nanodevice and desirable study of rich PDQD physical phenomena in graphene.