▎ 摘　　要

Graphene nanoribbons (GNRs) have seized strong interest. Recent studies show that domains of graphene in monolayer hexagonal boron nitride (h-BN) can be synthesized. Using the first principle calculations we have studied the electronic properties of armchair GNRs (AGNRs) confined by BN nanoribbons (BNNRs). While, H-terminated AGNRs have a close to zero bandgap with the width index of 3p+2, AGNRs confined by BNNRs exhibit a considerable bandgap. The bandgap opening is primarily due to perturbation to the on-site potentials of atoms at AGNR edges. A tight binding model is parameterized to confirm this mechanism and enable future device studies. (C) 2011 American Institute of Physics. [doi:10.1063/1.3571282]