Structural and electromagnetic properties of double C chains decorated zigzag silicene nanoribbon

Using the first-principles calculation, we investigate the structural and electromagnetic properties of the zigzag edge Si nanoribbons (ZSiNRs) decorated with double C chains. The results show that double C chains decorated ZSiNRs are always metallic independent of the ribbon width. The defect states contributed from double C chains are composed of two degenerated bands across the Fermi level. The perfect ZSiNR has a FM ground state, while double C chains decorated one have an AFM ground state. The C chains are always close to straight ones thereby resulting in a transverse contraction near the C chains and thus the ribbon width. The C–Si bond displays an ionic binding feature and the C–H bond is a typical covalent one because of the electronegativity and the bound force difference between H, C and Si atoms.