Charge neutral bilayer graphene has a gapped ground state as transport experiments demonstrate. One of the plausible such ground states is layered antiferromagnetic spin density wave (LAF) state, where the spins in top and bottom layers have same magnitude with opposite directions. We propose that lightly charged bilayer graphene in an electric field perpendicular to the graphene plane may be a half metal as a consequence of the inversion and particle-hole symmetry broken in the LAF state. We show this explicitly by using a mean field theory on a 2-layer Hubbard model for the bilayer graphene.
@article{arxiv.1302.7123,
title = {Half Metallic Bilayer Graphene},
author = {Jie Yuan and Dong-Hui Xu and Hao Wang and Yi Zhou and Jin-Hua Gao and Fu-Chun Zhang},
journal= {arXiv preprint arXiv:1302.7123},
year = {2013}
}