$C_3$ symmetry breaking metal-insulator transitions in a flat band in the half-filled Hubbard model on the decorated honeycomb lattice

Abstract

We study the single-orbital Hubbard model on the half-filled decorated honeycomb lattice. In the non-interacting theory at half-filling the Fermi energy lies within a flat band where strong correlations are enhanced. The lattice is highly frustrated. We find a correlation driven first-order metal-insulator transition to two different insulating ground states - a dimer valence bond solid Mott insulator when inter-triangle correlations dominate, and a broken ${\mathcal{C}}_3$-symmetry antiferromagnet that arises from frustration when intra-triangle correlations dominate. The metal-insulator transitions into these two phases have very different characters. The metal-broken ${\mathcal{C}}_3$ antiferromagnetic transition is driven by spontaneous ${\mathcal{C}}_3$ symmetry breaking that lifts the topologically required degeneracy at the Fermi energy and opens an energy gap in the quasiparticle spectrum. The metal-dimer valence bond solid transition breaks no symmetries of the Hamiltonian. It is caused by strong correlations renormalizing the electronic structure into a phase that is adiabatically connected to both the trivial band insulator and the ground state of the spin-1/2 Heisenberg model in the relevant parameter regime. Therefore, neither of these metal-insulator transitions can be understood in either the Brinkmann-Rice or Slater paradigms.

References in corpus (33)

• Magic-angle graphene superlattices: a new platform for unconventional superconductivity
• Correlated Insulator Behaviour at Half-Filling in Magic Angle Graphene Superlattices
• Correlated Electrons in High Temperature Superconductors
• Tuning superconductivity in twisted bilayer graphene
• Superconductors, Orbital Magnets, and Correlated States in Magic Angle Bilayer Graphene
• A Common Thread: the pairing interaction for the unconventional superconductors
• Theory of Intertwined Orders in High Temperature Superconductors
• Imaging Electronic Correlations in Twisted Bilayer Graphene near the Magic Angle
• Signatures of Gate-Tunable Superconductivity in Trilayer Graphene/Boron Nitride Moiré Superlattice
• Evidence of Gate-Tunable Mott Insulator in Trilayer Graphene-Boron Nitride Moiré Superlattice
• Tunable Moiré Bands and Strong Correlations in Small-Twist-Angle Bilayer Graphene
• Untying the insulating and superconducting orders in magic-angle graphene
• TRIQS: A Toolbox for Research on Interacting Quantum Systems
• Band touching from real space topology in frustrated hopping models
• Superconductivity without insulating states in twisted bilayer graphene stabilized by monolayer WSe${}_2$
• TRIQS/CTHYB: A Continuous-Time Quantum Monte Carlo Hybridization Expansion Solver for Quantum Impurity Problems
• Rotationally-invariant slave-boson formalism and momentum dependence of the quasiparticle weight
• Superconducting Two-Dimensional Metal-Organic Framework
• Strongly correlated superconductivity in a copper-based metal-organic framework with a perfect kagome lattice
• Absence of magnetic order for the spin-half Heisenberg antiferromagnet on the star lattice
• Topological Insulators on the Decorated Honeycomb Lattice
• Equivalence of Gutzwiller and slave-boson mean-field theories for multi-band Hubbard models
• Slave Boson Theory of Orbital Differentiation with Crystal Field Effects: Application to UO${}_2$
• Gutzwiller description of non-magnetic Mott insulators: a dimer lattice model
• Detecting spontaneous symmetry breaking in finite-size spectra of frustrated quantum antiferromagnets
• Manifestation of strongly correlated electrons in a 2D kagome metal-organic framework
• Tunable Bi-frustrated Electron Spin and Charge States in a Cu-Hexaaminobenzene Framework
• Spin-$\frac{1}{2}$ Heisenberg antiferromagnet on the star lattice: Competing valence-bond-solid phases studied by means of tensor networks
• Competing quantum paramagnetic ground states of the Heisenberg antiferromagnet on the star lattice
• Emergence of quasi-one-dimensional physics in Mo${}_3$S${}_7$(dmit)${}_3$, a nearly-isotropic three-dimensional molecular crystal
• Spin-$0$ Mott insulator to metal to spin-$1$ Mott insulator transition in the single-orbital Hubbard model on the decorated honeycomb lattice
• Multiple insulating phases due to the interplay of strong correlations and lattice geometry in a single-orbital Hubbard model
• Unconventional superconductivity near a flat band in organic and organometallic materials

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