Exactly solvable Kondo lattice model in the anisotropic limit
Exactly solvable Kondo lattice model in the anisotropic limit
复制标题
各向异性极限下精确可解的近藤晶格模型
DOI：
10.1103/physrevb.100.045148
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发表时间：
2019-07-30
影响因子：
3.7
通讯作者：
Zhong, Yin
中科院分区：
文献类型：
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作者：
Yang, Wei-Wei;Zhao, Jize;Zhong, Yin
本文引入了一个精确可解的Kondo格点模型，该模型没有任何微调的局域规范对称性。该模型描述了巡游电子通过纵向近藤交换与局域磁矩相互作用。它的可解性的结果从保守的本地化时刻在每个网站，是有效的任意晶格几何形状和电子填充。对正方形晶格的研究表明，在半填充时，基态是Neel反铁磁绝缘体。在有限温度下，发现了Mott绝缘体和关联金属的顺磁相，前者是具有强短程磁涨落的熔融反铁磁绝缘体，后者对应于Fermi类液体金属. MonteCarlo模拟和理论分析表明，从顺磁相到反铁磁绝缘体的转变是一个连续的二维伊辛转变。远离半填充，自旋条纹（非均匀磁序）在弱耦合，和强耦合相分离的模式进行了预测。通过建立伊辛反铁磁性和自旋条纹序，我们的模型可能与重费米子化合物CeCo（In 1-xHgx）（5）和隐藏有序化合物URu 2Si 2中的新量子液晶序有关。
In this paper we introduce an exactly solvable Kondo lattice model without any fine-tuning local gauge symmetry. This model describes itinerant electrons interplaying with a localized magnetic moment via only longitudinal Kondo exchange. Its solvability results from conservation of the localized moment at each site, and is valid for arbitrary lattice geometry and electron filling. A case study on a square lattice shows that the ground state is a Neel antiferromagnetic insulator at half-filling. At finite temperature, paramagnetic phases including a Mott insulator and correlated metal are found. The former is a melting antiferromagnetic insulator with a strong short-range magnetic fluctuation, while the latter corresponds to a Fermi liquidlike metal. Monte Carlo simulation and theoretical analysis demonstrate that the transition from paramagnetic phases into the antiferromagnetic insulator is a continuous two-dimensional Ising transition. Away from half-filling, patterns of spin stripes (inhomogeneous magnetic order) at weak coupling, and phase separation at strong coupling are predicted. With established Ising antiferromagnetism and spin stripe orders, our model may be relevant to a heavy fermion compound CeCo(In1-xHgx)(5) and novel quantum liquid-crystal order in a hidden order compound URu2Si2.