Half-metallicity in strained phosphorene nanoribbons

Abstract

We investigate the effect of nonuniform strains on the electronic properties of zigzag phosphorene nanoribbons (ZPNR) within a self-consistent computational model. We show that a nonuniform strain induces spin-splitting even at low values of strain. Moreover, a further increase of strain causes considerable spin splitting with a tunable spin-dependent energy gap until a critical value where the half-metallicity (HM) occurs. Interestingly, the black ZPNRs with different ribbon widths show the HM under out-of-plane tensile and in-plane compressive strains. Moreover, the critical values to realize HM can vary considerably depending on the ribbon width and the direction of strain. The results show that the nonuniform strain can be a practical way to enhance flexible spintronic in phosphorene-based devices.