R. R. Nair, I-Ling Tsai, M. Sepioni, O. Lehtinen, J. Keinonen, A. V. Krasheninnikov, A. H. Castro Neto, A. K. Geim, I. V. Grigorieva
A holy grail of spintronics is the control of magnetic properties by using electric fields. Finding a suitable material remains an elusive goal, with only a few imperfect candidates found so far. Graphene is a recent entry into the race due to its weak spin-orbit interaction, the ability to control its electronic properties by the electric field effect and the possibility to introduce paramagnetic centres such as vacancies and adatoms. Here we show that the defect magnetism is itinerant and can be controlled by doping, so that adatoms magnetic moments can be switched on and off. The much-discussed vacancy magnetism is found to contain two approximately equal contributions, one is coming from the same itinerant magnetism and the other is due to broken bonds. Our work suggests that graphene_s magnetism can be controlled by the field effect, similar to its transport or optical properties, and that spin diffusion length can be dramatically enhanced above a certain carrier density.
View original:
http://arxiv.org/abs/1301.7611
No comments:
Post a Comment