Abstract

We study the magnetic properties of graphene edges and graphene/graphane interfaces under the influence of electrostatic gates. For this an effective one-dimensional low-energy theory for the edge states, which is derived from the Hubbard model of the honeycomb lattice, is used. We first study the edge-state model in a mean-field approximation for the Hubbard Hamiltonian and show that it reproduces the results of the two-dimensional lattice theory. Quantum fluctuations around the mean-field theory of the effective one-dimensional model are treated by means of the bosonization technique in order to check the stability of the mean-field solution. We find that edge magnetism at graphene/graphane interfaces can be switched on and off by means of electrostatic gates. We describe a quantum phase transition between an ordinary and a ferromagnetic Luttinger liquid---a realization of itinerant one-dimensional ferromagnetism. This effect may provide means to experimentally discriminate between edge magnetism or disorder as the reason for a transport gap in very clean graphene nanoribbons.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.