2012/12/31 by Adolfo G. Grushin, Eduardo V. Castro, Alberto Cortijo +5 · 2 citations
Physics and Astronomy · #Advanced Condensed Matter Physics #Charge (physics) #Combinatorics #Condensed matter physics #Fermion #Honeycomb #Hubbard model #Lattice (music) #Materials science #Phase (matter) #Phase diagram #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Superconductivity #Symmetry breaking #Topological Materials and Phenomena #Topological quantum number #Topology (electrical circuits) #cond-mat.str-el #k-nearest neighbors algorithm
paper · pdf · doi:10.1103/physrevb.87.085136
published as Phys. Rev. B 87, 085136 (2013)
arxiv created 2012/12/31 · openalex publication_date 2013/02/28 · arxiv updated 2013/03/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study spontaneous symmetry breaking in a system of spinless fermions in the honeycomb lattice paying special emphasis to the role of an enlarged unit cell on time reversal symmetry broken phases. We use a tight-binding model with nearest-neighbor hopping t and Hubbard interaction V1 and V2 and extract the phase diagram as a function of electron density and interaction within a mean-field variational approach. The analysis completes the previous work done in Phys. Rev. Lett. 107, 106402 (2011) where phases with nontrivial topological properties were found with only a nearest-neighbor interaction V1 in the absence of charge decouplings. We see that the topological phases are suppressed by the presence of metallic charge density fluctuations. The addition of next to nearest-neighbor interaction V2 restores the topological nontrivial phases.