▎ 摘　　要

In this paper, we focus on a graphene heterojunction device: a Z-shaped graphene nanoribbon, which consists of two armchair leads and a zigzag junction. Based on the Landauer-Buttiker formula and the tight binding model, we found that the rectifying behavior can be achieved by applying an external gate voltage in the heterjunction region. We also found that the rectification effect is independent of junction width and length, it is an intrinsic property of the Z-junction graphene nanoribbon. This platform can be used to design and study functional graphene nanoscale devices. (C) 2008 American Institute of Physics.