Edge Conductance of Artificial Graphene Nanoribbons with Deterministic Chiral Edges on Si Substrates

The semiconductor-based artificial graphene (AG) promises versatile platforms for comprehensive explorations of graphene-like properties of Dirac Fermions and innovative device applications thanks to the deliberate control of the structure and the rich interactions of carriers. Here, the AG ribbon with a small lattice constant of 60 nm and predetermined chiral edges is achieved on Si substrates. Systematic studies of the temporal behavior of current at different bias voltages and magnetic fields demonstrate distinguished edge conductance of the AG ribbon, which can dominate the current in the AG ribbon. Moreover, the electric-field-dependent and magnetic-field-sensitive coupling between the edge and the bulk transport is disclosed. These phenomena are attributed to the carrier accumulation at the chiral edge, the current redistribution between the bulk and edge, and edge spin polarization. Our results unveil the unique one-dimensional (1D) edge transport, which may be generic in the AG and the graphene nanoribbons (GNRs) with the chiral edges. They also demonstrate that the AG ribbon can be a promising candidate for the exploration of the fundamental properties of the 1D ferromagnetic quantum spin chain and innovative spintronic devices.