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arXiv · 0909.1384

Half-Metallic Silicon Nanowires: Multiple Surface Dangling Bonds and Nonmagnetic Doping

Zhuo Xu·Qing-Bo Yan·Qing-Rong Zheng·Gang Su
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Abstract

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.

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Zhuo Xu, Qing-Bo Yan, Qing-Rong Zheng, Gang Su. 2009-09-08. Half-Metallic Silicon Nanowires: Multiple Surface Dangling Bonds and Nonmagnetic Doping. https://doi.org/10.1103/physrevb.80.081306

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