Spin negative differential resistance in edge doped zigzag graphene nanoribbons
Spin negative differential resistance in edge doped zigzag graphene nanoribbons
复制标题
边缘掺杂锯齿形石墨烯纳米带中的自旋负微分电阻
DOI：
10.1016/j.carbon.2013.11.017
复制
发表时间：
2014-03-01
期刊：
影响因子：
10.9
通讯作者：
Zhai, Ming-Xing
中科院分区：
文献类型：
--
作者：
Jiang, Chao;Wang, Xue-Feng;Zhai, Ming-Xing
采用密度泛函理论结合非平衡绿色函数方法，系统研究了边缘掺杂III族和V族元素的锯齿形石墨烯纳米带（ZGNRs）的非线性自旋相关输运性质.发现掺杂剂类型（受体或供体）以及几何对称性（奇或偶）对于确定电流的自旋极化和电流-电压特性至关重要。对于在下侧边缘上替代掺杂的ZGNR，在大约IV的偏置电压下，下（上）自旋电流在奇（偶）宽度ZGNR中占主导地位。值得注意的是，在由III族元素（B和Al）掺杂的偶宽度ZGNR中，仅对于下自旋发生负微分电阻（NDR）。自旋负阻的偏置范围随ZGNR宽度的增加而增大。无论是在奇数宽度的ZGNR中还是在V族元素（N和P）掺杂的偶数宽度的ZGNR中，都没有观察到明显的自旋NDR。这种特殊的自旋负阻边缘掺杂的ZGNRs表明在自旋电子学的潜在应用。(C)2013爱思唯尔有限公司保留所有权利。
The nonlinear spin-dependent transport properties in zigzag graphene nanoribbons (ZGNRs) edge doped by an atom of group III and V elements are studied systematically using density functional theory combined with non-equilibrium Green's functions. The dopant type, acceptor or donor, and the geometrical symmetry, odd or even, are found critical in determining the spin polarization of the current and the current-voltage characteristics. For ZGNRs substitutionally doped on the lower-side edge, the down (up) spin current dominates in odd-(even-) width ZGNRs under a bias voltage around 1 V. Remarkably, in even-width ZGNRs, doped by group III elements (B and Al), negative differential resistance (NDR) occurs only for down spins. The bias range of the spin NDR increases with the width of ZGNRs. The clear spin NDR is not observed in any odd-width ZGNRs nor in even-width ZGNRs doped by group V elements (N and P). This peculiar spin NDR of edge doped ZGNRs suggests potential applications in spintronics. (C) 2013 Elsevier Ltd. All rights reserved.