Oxygen-induced spin-polarized ferromagnetic state of a 1D CuO nanowire

With the full potential linearized augmented plane wave (FLAPW) method, we have investigated if a 1D Cu nanowire can display spin polarized phase. Interestingly, it was obtained that the oxygen has dramatic effect on the magnetic state manifesting spin polarized ferromagnetic ground state for free standing CuO wire, whereas pure unsupported 1D Cu wire has non-magnetic state. Our numerical results show that the magnetic moments of Cu and O atoms are very sensitive to the inter-atomic distance between Cu and O atoms, while the sum of magnetic moments from Cu and O atoms are almost constant in the range of plastic deformation. In addition, it was displayed that spin polarized 1D CuO nanowires were shown to have nearly half metallic features. We also extracted the yield stress of the CuO nanowires, and found that the maximum plastic deformation occurred at the inter-atomic distance of 3.8 a.u. between Cu and O atoms. In addition, the ferromagnetic CuO nanowires prefer perpendicular magnetization to the chain axis fro most Cu-O interatomic distances.