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arXiv · 1208.1355

Bipolar Magnetic Semiconductors: A New Class of Spintronics Materials

Xingxing Li·Xiaojun Wu·Zhenyu Li·Jinlong Yang·J. G. Hou
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Abstract

Electrical control of spin polarization is very desirable in spintronics, since electric field can be easily applied locally in contrast with magnetic field. Here, we propose a new concept of bipolar magnetic semiconductor (BMS) in which completely spin-polarized currents with reversible spin polarization can be created and controlled simply by applying a gate voltage. This is a result of the unique electronic structure of BMS, where the valence and conduction bands possess opposite spin polarization when approaching the Fermi level. Our band structure and spin-polarized electronic transport calculations on semi-hydrogenated single-walled carbon nanotubes confirm the existence of BMS materials and demonstrate the electrical control of spin-polarization in them.

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Xingxing Li, Xiaojun Wu, Zhenyu Li, Jinlong Yang, J. G. Hou. 2012-08-07. Bipolar Magnetic Semiconductors: A New Class of Spintronics Materials. https://doi.org/10.1039/c2nr31743e

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