Effects of hole doping and strain on magnetism in buckled phosphorene and arsenene

Phosphorene and arsenene are newly discovered two-dimensional semiconductors with many exciting physical properties. Here, using first-principles density functional theory, we investigate the effects of hole doping and strain on the magnetism in phosphorene and arsenene with buckled structures. We show that ferromagnetic ground states originating from Stoner instability can emerge in a broad range of hole concentrations. In addition, strain effectively modulates the magnetism by means of changing the band orders of the top of the valence bands. Magnetoresponses under hole doping and strain in buckled phosphorene and arsenene are distinct due to the contrary band orders at their native states. Furthermore, magnetoelastic coupling effect and magnetostriction in buckled phosphorene and arsenene are discussed. Our results suggest the great potential of buckled phosphorene and arsenene in magnetic device applications.