Jung J, Pereg-Barnea T, Macdonald A H
Department of Physics, University of Texas at Austin, Austin, Texas 78712, USA.
Phys Rev Lett. 2009 Jun 5;102(22):227205. doi: 10.1103/PhysRevLett.102.227205.
A graphene nanoribbon with zigzag edges has a gapped magnetic ground state with an antiferromagnetic interedge superexchange interaction. We present a theory based on asymptotic properties of the Dirac-model ribbon wave function which predicts W-2 and W-1 ribbon-width dependencies for the superexchange interaction strength and the charge gap, respectively. We find that, unlike the case of conventional atomic-scale superexchange, opposite spin orientations on opposite edges of the ribbon are favored by both kinetic and interaction energies.
具有锯齿形边缘的石墨烯纳米带具有带隙的磁基态，存在反铁磁边缘间超交换相互作用。我们提出了一种基于狄拉克模型带状波函数渐近性质的理论，该理论分别预测了超交换相互作用强度和电荷隙对W - 2和W - 1带宽度的依赖性。我们发现，与传统原子尺度超交换的情况不同，纳米带相对边缘上相反的自旋取向在动能和相互作用能方面都更有利。
