Tuning the electronic and magnetic properties of the Si nanoribbons through dangling bond

Combined with three spin configurations, the effects of the dangling bonds on the electronic and magnetic properties of both zigzag edge and armchair edge Si nanoribbions (ZSiNR and ASiNR) have been investigated systematically by the first-principles calculations in the local spin-density function theory. The dangling bonds at one edge or both edges make ZSiNR to transform from ferromagnetic state of the perfect ZSiNR to antiferromagnetic state. However, the dangling bonds at one edge and both edges make ASiNR to transform from nonmagnetic semiconductor of the perfect ASiNR to ferromagnetic and antiferromagnetic metals, respectively. Furthermore, the magnetic moment of the ferromagnetic state increases for the perfect bare one edge and bare both edges successively for either ZSiNR or ASiNR. (C) 2010 Elsevier B.V. All rights reserved.