Unconventional Deformation Potential and Half-Metallicity in Zigzag Nanoribbons of 2D-Xenes

Realization of half-metallicity (HM) in low dimensional materials is a fundamental challenge for nano spintronics, which is a critical component for developing alternative generations of information technology. Using first-principles, we reveal unconventional deformation potential for zigzag 2D-Xenes nanoribbons (NRs). Both the conduction band minimum (CBM) and valence band maximum (VBM) of the edge states are of negative deformation potentials. This unique property, combined with the localization and spin-polarization of the edge states, enable us to induce spin-splitting and the HM by inhomogeneous strain pattern, such as a simple in-plane bending. Indeed, our calculation using the generalized Bloch theorem reveals the predicted HM in bent zigzag silicene NRs. Furthermore, the magnetic stability of the long range magnetic order for the spin-polarized edge states is maintained well against the bending deformation. These aspects indicate that it is a promising approach to realize the HM in low dimensions with the zigzag 2D-Xenes NRs.