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arXiv · 1305.2993

Spin-polarized bandgap of graphene induced by alternative chemisorption with MgO (111) substrate

Sung Beom Cho·Yong-Chae Chung
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Abstract

Using First-principle calculations, substrate effect of O-terminated (rt3 x rt3) MgO (111) on graphene was investigated for spintronics application. Surprisingly, the graphene can be turned into a spin-polarized semiconductor, which implies that the totally spin-polarized current can be generated and its on/off switching can be also controlled. The origin of the spin-polarized band structure is spin-ordering due to alternative sp2-sp3 covalent bondings induced by the MgO (111) substrate. The results indicate that the tailored pattern of the chemisorption can be highly efficient or introducing totally spin-polarized current to the graphene.

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Sung Beom Cho, Yong-Chae Chung. 2013-11-26. Spin-polarized bandgap of graphene induced by alternative chemisorption with MgO (111) substrate. https://arxiv.org/abs/1305.2993

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