Topological Fermi Liquids from Coulomb Interactions in the Doped Honeycomb Lattice

Eduardo V. Castro, Adolfo G. Grushin, Belén Valenzuela, María A. H. Vozmediano, Alberto Cortijo, Fernando de Juan
2011 Physical Review Letters  
We get an anomalous Hall metallic state in the Honeycomb lattice with nearest neighbors only arising as a spontaneously broken symmetry state from a local nearest neighbor Coulomb interaction V . The key ingredient is to enlarge the unit cell to host six atoms that permits Kekul\'e distortions and supports self-consistent currents creating non trivial magnetic configurations with total zero flux. We find within a variational mean field approach a metallic phase with broken time reversal
more » ... (T) very close in parameter space to a Pomeranchuk instability. Within the T broken region the predominant configuration is an anomalous Hall phase with non zero Hall conductivity, a realization of a topological Fermi liquid. A T broken phase with zero Hall conductivity is stable in a small region of the parameter space for lower values of V .
doi:10.1103/physrevlett.107.106402 pmid:21981516 fatcat:2ky555uaofbu3ges7nbq23uply