Strain-induced effects in zigzag-edged blue phosphorene nanoribbons with edge sulfur passivation

Abstract

Motivated by the recent successful growth of quasi-free-standing single layer blue phosphorus (BlueP) on tellurium functionalized Au(1 1 1) by using black phosphorus as the precursor (Zhang et al 2016 Nano Lett. 16 4903; Gu et al 2017 ACS Nano 11 4943), here we study the strain performance for zigzag BlueP nanoribbons (zBluePNRs) with different edge chemical modifications. Based on the first-principles calculations, interestingly, we find that a narrow zBluePNR of width up to ∼2 nm with edge sulfur (S) passivation under an uniaxial strain exhibits an important effect of negative Poisson’s ratio because of the particularity of the P–S bonds at edges, and as the ribbon width further increases the Poisson’s ratio varies from negative to positive. Meanwhile, the S-passivation also induces magnetism, and applying a strong enough strain can transfer this zBluePNR from magnetic metal state to half-metal one. All these physical properties are discussed in connection with the variation of microstructure of the ribbons. Our findings may paving the way for both a fundamental understanding of nanoscale physics and applied device engineering.