Four-Spin Terms and the Origin of the Chiral Spin Liquid in Mott Insulators on the Triangular Lattice
Four-Spin Terms and the Origin of the Chiral Spin Liquid in Mott Insulators on the Triangular Lattice
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DOI：
10.1103/physrevlett.127.087201
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发表时间：
2021-08-19
影响因子：
8.6
通讯作者：
Moore, Joel E.
中科院分区：
文献类型：
--
作者：
Cookmeyer, Tessa;Motruk, Johannes;Moore, Joel E.
在强排斥下，三角格子Hubbard模型由s = 1/2自旋和最近邻反铁磁海森堡相互作用描述，并表现出常规的120度阶。使用无限密度矩阵重整化群和精确对角化，我们研究了额外的四自旋相互作用的影响，自然产生的基础莫特绝缘体物理的电子的排斥力减少。虽然这些相互作用在历史上一直与无隙基态与新兴自旋费米表面，我们发现，在物理相关的参数，他们稳定的手征自旋液体（CSL）的Kalmeyer-Laughlin（KL）型，澄清在哈伯德模型的最新研究中的观察。然后，我们提出了一个自洽的解决方案的基础上的平均场重写的相互作用，以获得一个哈密顿量的KL状态的父哈密顿量的相似性，提供了一个物理的理解CSL的起源。
At strong repulsion, the triangular-lattice Hubbard model is described by s = 1/2 spins with nearest-neighbor antiferromagnetic Heisenberg interactions and exhibits conventional 120 degrees order. Using the infinite density matrix renormalization group and exact diagonalization, we study the effect of the additional four-spin interactions naturally generated from the underlying Mott-insulator physics of electrons as the repulsion decreases. Although these interactions have historically been connected with a gapless ground state with emergent spinon Fermi surface, we find that, at physically relevant parameters, they stabilize a chiral spin liquid (CSL) of Kalmeyer-Laughlin (KL) type, clarifying observations in recent studies of the Hubbard model. We then present a self-consistent solution based on a mean-field rewriting of the interaction to obtain a Hamiltonian with similarities to the parent Hamiltonian of the KL state, providing a physical understanding for the origin of the CSL.