Hydrogen saturation stabilizes vacancy-induced ferromagnetic ordering in graphene.
Density functional theory calculations are performed to explore vacancy-induced magnetism in graphene. The hydrogen saturation not only stabilizes the vacancy structure but also induces distinct magnetic coupling depending on the defect distribution: weak magnetic coupling between defects on different sublattices and strong coupling between defects on the same sublattice. Ferromagnetic ordering has to be accompanied with a semiconducting property. The interaction integral J between defective spins decreases linearly with the increase of the distance between them. Based on the 2D Ising model and Monte Carlo simulations, the possible highest Curie temperature T(c) of defective graphene is predicted to be lower than 500 K.
Li
Weifeng
W
School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore.
Zhao
Mingwen
M
Zhao
Xian
X
Xia
Yueyuan
Y
Mu
Yuguang
Y
D002244:Carbon / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry; D006859:Hydrogen / Q000737:chemistry*; D008280:Magnetics; D009010:Monte Carlo Method; D011522:Protons; D013696:Temperature
D005290:Ferric Compounds; D011522:Protons; C001215:ferrite; D002244:Carbon; D006859:Hydrogen