Magnetization due to localized states on graphene grain boundary.
Magnetization due to localized states on graphene grain boundary.
复制标题
DOI：
10.1038/srep11744
复制
发表时间：
2015-07-06
影响因子：
4.6
通讯作者：
Wakabayashi K
中科院分区：
文献类型：
--
作者：
Dutta S;Wakabayashi K
已经发现石墨烯中的磁性源自各种缺陷，例如，空位，边缘形成，添加原子等。在这里，我们讨论了通过晶界在石墨烯中实现磁性的替代路线。在化学气相沉积石墨烯的过程中，多个石墨烯成核中心独立生长，并面对不寻常的键合环境，从而导致晶界的形成。我们调查的起源磁性在这样的晶界内的第一性原理计算，通过让两个成核中心相互作用，在他们的界面。我们观察到前所未有的点缺陷的形成，由稠合的三元和更大的碳环组成，其诱导石墨烯量子点的净磁化。在周期晶格的情况下，点缺陷阵列的出现导致磁性晶界的形成。这些缺陷上的净磁化由于偏离原始石墨烯的二分特性而产生。我们观察到磁性晶界诱导的色散较少的平坦带附近的费米能，显示出较高的本地化的电子。这些平带可以通过少量掺杂来获得，从而增强磁性。此外，晶界还可以诱导沿着晶界方向的非对称自旋导电行为。这些特性可用于传感器和自旋过滤应用。
Magnetism in graphene has been found to originate from various defects, e.g., vacancy, edge formation, add-atoms etc. Here, we discuss about an alternate route of achieving magnetism in graphene via grain boundary. During chemical vapor deposition of graphene, several graphene nucleation centers grow independently and face themselves with unusual bonding environment, giving rise to the formation of grain boundaries. We investigate the origin of magnetism in such grain boundaries within first-principles calculations, by letting two nucleation centers interact with each other at their interface. We observe formation of unprecedented point defect, consisting of fused three-membered and larger carbon rings, which induces net magnetization to graphene quantum dots. In case of periodic lattices, the appearance of array of point defects leads to the formation of magnetic grain boundaries. The net magnetization on these defects arises due to the deviation from bipartite characteristics of pristine graphene. We observe magnetic grain boundary induced dispersion less flat bands near Fermi energy, showing higher localization of electrons. These flat bands can be accessed via small doping, leading to enhanced magnetism. Moreover, the grain boundaries can induce asymmetric spin conduction behavior along the cross boundary direction. These properties can be exploited for sensor and spin-filtering applications.
登录
查看更多内容
影响因子：
3.3
作者：
Biro, Laszlo P.;Lambin, Philippe
通讯作者：
Lambin, Philippe
影响因子：
38.3
作者：
Lahiri, Jayeeta;Lin, You;Batzill, Matthias
通讯作者：
Batzill, Matthias
影响因子：
64.8
作者：
Hashimoto, A;Suenaga, K;Iijima, S
通讯作者：
Iijima, S
影响因子：
10.9
作者：
Dutta, Sudipta;Pati, Swapan K.
通讯作者：
Pati, Swapan K.
在液态铜表面生长均匀的六角形石墨烯薄片和薄膜
DOI：
10.1073/pnas.1200339109
发表时间：
2012-05-22
影响因子：
11.1
作者：
Geng, Dechao;Wu, Bin;Liu, Yunqi
通讯作者：
Liu, Yunqi