Magnetism and perfect spin filtering effect in graphene nanoflakes
Magnetism and perfect spin filtering effect in graphene nanoflakes
复制标题
DOI：
10.1088/0957-4484/21/38/385201
复制
发表时间：
2010-09-24
期刊：
影响因子：
3.5
通讯作者：
Guo, H.
中科院分区：
文献类型：
--
作者：
Sheng, W.;Ning, Z. Y.;Guo, H.
利用第一性原理计算方法研究了锯齿状石墨烯纳米片的磁性和自旋极化输运性质。铁磁结构被发现是三角形石墨烯薄片的基态。通过将B或N原子掺杂到薄片中来削弱磁性，并且如果在薄片的某些亚晶格中掺杂F原子，则磁性增强。磁性可以通过掺杂剂的行为以及掺杂剂与主体原子之间的相互作用来合理化。对于夹在两个金电极之间的纯的或B掺杂的石墨烯薄片，实现了完美（100%）的自旋过滤效果。自旋电流的方向被发现是翻转，如果薄片掺杂N，O，或F原子。取向可调的自旋过滤效应在实际应用中具有潜在的应用价值。
Magnetic and spin-polarized transport properties in zigzag-edged graphene nanoflakes were investigated from first-principles calculations. Ferrimagnetic structure was found to be the ground state for triangular shaped graphene flakes. Magnetism is weakened by doping B or N atoms into the flakes, and it is enhanced if F atoms are doped in certain sublattices of the flakes. The magnetic properties can be rationalized by the behaviors of dopants as well as interactions between dopants and the host atoms. A perfect (100%) spin filtering effect was achieved for the pure or B doped graphene flake sandwiched between two gold electrodes. The orientation of the spin current is found to be flipped if the flake is doped with N, O, or F atoms. The orientation-tunable spin filtering effect is potentially useful in practical applications.