Quantum spin liquid emerging from correlated relativistic fermions in two dimensions
Prof. Dr. Alejandro Muramatsu (Universität Stuttgart)
Free fermions on a two dimensional honeycomb lattice, as in graphene, have at low energies a dispersion relation like massless relativistic fermions. Here we show, that correlations lead to a gapped spin liquid emerging between the state described by massless Dirac fermions and an antiferromagnetically ordered Mott insulator. This quantum-disordered state is found to be a short-range resonating valence-bond liquid, akin to the one proposed for high-temperature superconductors.