Formation of quantum dot in graphene single nanoconstriction

摘要

We report the experimental and theoretical investigation of single carrier transport property on graphene single-constriction devices. As the Fermi wavelength is comparable with the width of the constriction and shorter than the length of the constriction in our device, the single quantum dot-dominated characteristic is observed by back-gate modulation. The first-principles calculation shows that discrete states are induced in the narrower constriction due to the mode mixing in the narrower constriction and wider leads. It is found that the geometry of constriction-wider lead junctions plays a crucial role in single-dot formation in graphene constriction structure. (C) 2019 The Japan Society of Applied Physics