Tao Hong-Shuai, Chen Yao-Hua, Lin Heng-Fu, Liu Hai-Di, Liu Wu-Ming
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Sci Rep. 2014 Jun 20;4:5367. doi: 10.1038/srep05367.
Bilayer honeycomb lattice, with inter-layer tunneling energy, has a parabolic dispersion relation, and the inter-layer hopping can cause the charge imbalance between two sublattices. Here, we investigate the metal-insulator and magnetic phase transitions on the strongly correlated bilayer honeycomb lattice by cellular dynamical mean-field theory combined with continuous time quantum Monte Carlo method. The procedures of magnetic spontaneous symmetry breaking on dimer and non-dimer sites are different, causing a novel phase transition between normal anti-ferromagnet and layer anti-ferromagnet. The whole phase diagrams about the magnetism, temperature, interaction and inter-layer hopping are obtained. Finally, we propose an experimental protocol to observe these phenomena in future optical lattice experiments.
具有层间隧穿能量的双层蜂窝晶格具有抛物线型色散关系，且层间跃迁会导致两个子晶格之间的电荷失衡。在此，我们通过元胞动力学平均场理论结合连续时间量子蒙特卡罗方法，研究强关联双层蜂窝晶格上的金属 - 绝缘体和磁相变。二聚体和非二聚体位点上磁自发对称破缺的过程不同，导致了正常反铁磁体和层状反铁磁体之间的一种新型相变。得到了关于磁性、温度、相互作用和层间跃迁的完整相图。最后，我们提出了一个实验方案，以便在未来的光学晶格实验中观测这些现象。
