By means of first-principles density functional theory calculations, we find that hydrogen-passivated ultrathin silicon nanowires (SiNWs) along [100] direction with symmetrical multiple surface dangling bonds (SDBs) and boron doping can have a half-metallic ground state with 100% spin polarization, where the half-metallicity is shown quite robust against external electric fields. Under the circumstances with various SDBs, the H-passivated SiNWs can also be ferromagnetic or antiferromagnetic semiconductors. The present study not only offers a possible route to engineer half-metallic SiNWs without containing magnetic atoms but also sheds light on manipulating spin-dependent properties of nanowires through surface passivation.
@article{arxiv.0909.1384,
title = {Half-Metallic Silicon Nanowires: Multiple Surface Dangling Bonds and Nonmagnetic Doping},
author = {Zhuo Xu and Qing-Bo Yan and Qing-Rong Zheng and Gang Su},
journal= {arXiv preprint arXiv:0909.1384},
year = {2009}
}