Effect of vacancy defects on electronic and magnetic properties of zigzag silicon nanoribbons

we investigate the electronic and magnetic characteristics of the zigzag silicon nanoribbons (ZSiNRs) having a monovacancy or a divacancy by the first-principles calculations based on density-functional theory. No matter a monovacancy or a divacancy, a direct semiconductor ZSiNRs turn to a metallic character, but when the vacancy is at different position, there is a different magnetic properties. The ZSiNRs become metallic no matter a monovacancy or divacancy after relaxation, when the vacancy is at the center, they have antiferromagnetic property, while they have ferromagnetic property in non-center.