Sichau, J Resonance Microwave Measurements of an Intrinsic Spin-Orbit Coupling Gap in Graphene: A Possible Indication of a Topological State. [electronic resource] - Physical review letters Feb 2019 - 046403 p. digital Publication Type: Journal Article ISSN: 1079-7114 Standard No.: 10.1103/PhysRevLett.122.046403 doi