▎ 摘　　要

We study the quasi-bound state and the transport properties in the T-shaped graphene nanoribbon consisting of a metallic armchair-edge ribbon connected to a zigzag-edge sidearm. We systematically study the condition under which there are quasi-bound states in the system for a wide range of the system size. It is found that when the width of the sidearm is about half of the width of the armchair graphene nanoribbon, there is a quasi-bound state trapped at the intersection of the T-shaped structure. The quasi-bound states are truly localized in the sidearm but have small continuum components in the armchair graphene nanoribbons. The quasi-bound states have strong effect on the transport between the armchair leads through the Fano effect, but do not affect the transport between the armchair lead and the sidearm. (C) 2013 AIP Publishing LLC.