Vanhala Tuomas I, Siro Topi, Liang Long, Troyer Matthias, Harju Ari, Törmä Päivi
COMP Centre of Excellence, Department of Applied Physics, Aalto University, Helsinki, Finland.
Theoretische Physik, ETH Zurich, 8093 Zurich, Switzerland.
Phys Rev Lett. 2016 Jun 3;116(22):225305. doi: 10.1103/PhysRevLett.116.225305. Epub 2016 Jun 2.
Using dynamical mean-field theory and exact diagonalization we study the phase diagram of the repulsive Haldane-Hubbard model, varying the interaction strength and the sublattice potential difference. In addition to the quantum Hall phase with Chern number C=2 and the band insulator with C=0 present already in the noninteracting model, the system also exhibits a C=0 Mott insulating phase, and a C=1 quantum Hall phase. We explain the latter phase by a spontaneous symmetry breaking where one of the spin components is in the Hall state and the other in the band insulating state.
利用动力学平均场理论和精确对角化方法，我们研究了排斥性霍尔丹 - 哈伯德模型的相图，改变相互作用强度和子晶格势差。除了非相互作用模型中已存在的陈数(C = 2)的量子霍尔相和(C = 0)的带绝缘体相之外，该系统还展现出(C = 0)的莫特绝缘相和(C = 1)的量子霍尔相。我们通过自发对称性破缺来解释后一个相，其中一个自旋分量处于霍尔态，另一个处于带绝缘态。
