Sharma SRKC Yamijala, Swapan K Pati
Spin-polarized first-principles calculations have been performed on zigzag Boron-Nitride Nanoribbons (z-BNNRs) with lines of alternating fused pentagon (P) and heptagon (H) rings (Pentagon-Heptagon-line-defect) at single edge as well as at both edges. The number of line (n) of the Pentagon-Heptagon-defect has been varied from 1 to 8 for 10-zBNNRs. Among the different spin-configurations which we have studied, we find that, the spin-configuration with ferromagnetic ordering at each edge and anti-ferromagnetic ordering across the edges is quite interesting. For this spin-configuration, we find that, if the introduced PH-line-defect is odd numbered, the systems behave as spin-polarized semi-conductors, but, for even numbered, all the systems show interesting anti-ferromagnetic half-metallic behavior. Robustness of these results has been cross checked by the variation of the line-defect position and also by the variation of the width [from ~ 1.1 nm (6-zBNNR) to ~ 3.3 nm (16-zBNNR)] of the ribbon. Density of States (DOS), projected-DOS and band-structure analysis have been accomplished to understand the reasons for these differences between even and odd-line-defects. The main reason for many of the observed changes was traced back to the change in edge nature of the BNNR, which indeed dictates the properties of the systems.
View original:
http://arxiv.org/abs/1306.5049
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