Electronic and magnetic properties of honeycomb arsenic-phosphorus nanoribbons via a first-principles study

In this paper, the structural stability, electronic structure, and magnetic properties of single-layer honeycomb arsenic??? phosphorus (AsP) nanoribbons are systematically investigated using density functional theory calculations. Zigzag AsP nanoribbons (ZNRs) possess magnetic moments on the edge atoms. In addition, the ferromagnetic and intraedge antiferromagnetic states of ZNRs can be randomly coupled because of their equal total energy and almost identical electronic band structures. Armchair AsP nanoribbons (ANRs) show clear edge reconstructions and are nonmagnetic. ZNRs and ANRs are indirect and direct semiconductors, respectively, and have significantly smaller bandgaps than that of two-dimensional single-layer AsP due to their edge states. More interestingly, when the edge atoms are saturated by hydrogen atoms, ZNRs change from an indirect bandgap to a direct bandgap. In addition, both the ZNRs and ANRs exhibit enlarged bandgaps and nonmagnetic ground states due to hydrogen saturation. This work indicates that AsP nanoribbons can possess quite different electronic structures from two-dimensional single-layer AsP, extending the application field of AsP nanostructures.