▎ 摘　　要

Quantum transport calculations show that a transport gap approximately E-g = 2hv(F)/W can be engineered in graphene using two parallel transport barriers, separated by W, extended along the zigzag direction. The barriers, modeled by chemically decorated observed line defects, create confinement and resonance bands tracing the bands in zigzag nanoribbons. The resonance bands terminate at the dimensional crossover, where the states become boundary-localized, leaving the transport gap. The structure also allows for nearly perfect valley polarization.