Ferrimagnetically ordered states in the Hubbard model on the hexagonal golden-mean tiling
Ferrimagnetically ordered states in the Hubbard model on the hexagonal golden-mean tiling
复制标题
六边形黄金分割平铺哈伯德模型中的亚铁磁性有序态
DOI：
10.1103/physrevb.105.104410
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发表时间：
2022
影响因子：
3.7
通讯作者：
S. Coates
中科院分区：
文献类型：
--
作者：
A. Koga;S. Coates
研究了二维六角Goldenmean镶嵌上半填充Hubbard模型的磁性。我们发现，镶嵌的顶点模型是二分的，子晶格不平衡为π 5/（6 τ 3）（其中τ是黄金平均值），而非相互作用紧束缚模型给出了E = 0的宏观简并态.我们澄清，每个子晶格有特定类型的受限状态，这反过来又导致了一个有趣的空间图案在弱耦合制度的局部磁化。此外，我们还得到了束缚态分数的下界为（τ +9）/（6 τ 6）<$0.0986，并证明了这是一个精确的分数。这些结果意味着即使在弱耦合极限下也能实现亚铁磁有序态。库仑相互作用的引入提高了费米能级的宏观简并度，在均匀磁化的同时也产生了有限的交错磁化。同样，磁化强度的空间分布随着相互作用强度的增加而连续变化。在磁有序态的交叉行为也解决了在垂直空间分析。
We study magnetic properties of the half-filled Hubbard model on the two-dimensional hexagonal goldenmean tiling. We find that the vertex model of the tiling is bipartite, with a sublattice imbalance of √ 5/(6τ3) (where τ is the golden mean), and that the non-interacting tight-binding model gives macroscopically degenerate states at E = 0. We clarify that each sublattice has specific types of confined states, which in turn leads to an interesting spatial pattern in the local magnetizations in the weak coupling regime. Furthermore, this allows us to analytically obtain the lower bound on the fraction of the confined states as (τ + 9)/(6τ6) ∼ 0.0986, which is conjectured to be the exact fraction. These results imply that a ferrimagnetically ordered state is realized even in the weak coupling limit. The introduction of the Coulomb interaction lifts the macroscopic degeneracy at the Fermi level, and induces finite staggered magnetization as well as uniform magnetization. Likewise, the spatial distribution of the magnetizations continuously changes with increasing interaction strength. The crossover behavior in the magnetically ordered states is also addressed in terms of the perpendicular space analysis.
影响因子：
41.2
作者：
Deguchi, Kazuhiko;Matsukawa, Shuya;Ishimasa, Tsutomu
通讯作者：
Ishimasa, Tsutomu