▎ 摘　　要

Stimulated by recent advances in isolating graphene, the authors discovered that a quantum dot can be trapped in a Z-shaped graphene nanoribbon junction. The topological structure of the junction can completely confine electronic states. By varying the junction length, the authors can alter the spatial confinement and the number of discrete levels within the junction. In addition, a quantum dot can be realized regardless of substrate induced static disorder or irregularities on the edges of the junction. The method can be used to easily design quantum dot devices. The authors also provide a platform to design zero-dimensional functional nanoscale electronic devices using graphene ribbons. (c) 2007 American Institute of Physics.