论文标题
$ c_3 $在装饰的蜂窝晶格上半填充的哈伯德模型中的平坦乐队中的对称破坏金属绝缘体过渡
$C_3$ symmetry breaking metal-insulator transitions in a flat band in the half-filled Hubbard model on the decorated honeycomb lattice
论文作者
论文摘要
我们研究了半填充装饰的蜂窝晶格的单轨式哈伯德模型。在半填充的非相互作用理论中，费米能量在一个平坦的频段内，在那里增强了强相关性。晶格非常沮丧。我们发现相关驱动的一阶金属构造器过渡到两个不同的绝缘接地状态 - 当三角形相关性占主导地位时，二聚体价值键固体mott绝缘子，而$ \ nathcal {c} _3 $ symmmetry抗fiferromagnet均来自静脉内的静脉曲张correlation-greelation-greelation-trientation-trimate-trimantry antiferomagnet。金属 - 胰岛素过渡到这两个阶段的特征非常不同。金属破裂的$ \ MATHCAL {C} _3 $抗铁磁过渡是由自发的$ \ Mathcal {C} _3 $对称破坏驱动的，从而提高了Fermi能量的拓扑所需的退化，并在Quasiparticle spectrum spectrum spectrum spectrum spectrum。金属二聚体键粘结固体过渡不会破坏哈密顿量的对称性。它是由将电子结构重新归一化的强相关性引起的，该相位在相关参数状态下绝热连接到微不足道带绝缘子和Spin-1/2 Heisenberg模型的基态。因此，在Brinkmann-Rice或Slater范式中都无法理解这两种金属 - 绝缘体转变。
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.
