Hefei National Laboratory of Physical Science at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
Nanoscale. 2012 Sep 21;4(18):5680-5. doi: 10.1039/c2nr31743e. Epub 2012 Aug 9.
Electrical control of spin polarization is very desirable in spintronics, since electric fields can be easily applied locally, in contrast to magnetic fields. Here, we propose a new concept of bipolar magnetic semiconductors (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. BMS is thus expected to have potential for various applications. 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.
在自旋电子学中，电控制自旋极化是非常理想的，因为电场可以很容易地局部施加，而磁场则不然。在这里，我们提出了一种新的双极磁性半导体（BMS）的概念，通过施加栅极电压，可以简单地产生和控制完全自旋极化的电流，并实现其自旋极化的可逆性。这是 BMS 独特的电子结构的结果，其中价带和导带在接近费米能级时具有相反的自旋极化。因此，BMS 有望在各种应用中具有潜力。我们对半氢化单壁碳纳米管的能带结构和自旋极化电子输运计算证实了 BMS 材料的存在，并证明了它们的自旋极化的电控制。
