Eur. Phys. J. B (2016) 89: 205
https://doi.org/10.1140/epjb/e2016-70212-6

Regular Article

Magnetic interactions between vacancy-induced intrinsic magnetic impurities in single-wall carbon nanotubes

¹ Department of Physics, Beijing Normal University, Beijing 100875, P.R. China
² Department of Physics, Hebei Normal University, Hebei 050024, P.R. China

^a e-mail: liang@bnu.edu.cn

Received: 9 April 2016
Received in final form: 3 June 2016
Published online: 21 September 2016

Abstract

Spin-half paramagnetism induced by point detects was found in graphene recently, micromechanism of this magnetic response can be explained well by the intrinsic magnetic impurity theory. In this paper, we apply this theory to two types of single-walled carbon nanotubes (SWCNs) and calculate the properties of various magnetic interactions for comparison. Interestingly, magnetic interactions have different behaviors in these systems. Following our calculation, within a short length, the interactions can be suppressed by ether size effect or a tiny band gap, and then exhibit exponentially decaying. However, in the absence of a band gap, the RKKY interaction could leave a tiny tail at long range, which determines long range magnetic order. Further more, when a tiny band gap exist in the systems, the Heisenberg coupling is the dominate one due to the expanded wavefunction. According to these result, vacancy states in different types of SWCNs could form different magnetic order, bringing abundant candidates for application.