Quantum paramagnetic states in the spin-1/2 distorted honeycomb-lattice Heisenberg antiferromagnet - application to Cu2(pymca)3(ClO4) -
Quantum paramagnetic states in the spin-1/2 distorted honeycomb-lattice Heisenberg antiferromagnet - application to Cu2(pymca)3(ClO4) -
复制标题
自旋 1/2 扭曲蜂窝晶格海森堡反铁磁体中的量子顺磁态 - 应用于 Cu2(pymca)3(ClO4) -
DOI：
10.1103/physrevb.106.134410
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发表时间：
2022
影响因子：
3.7
通讯作者：
Hagiwara Masayuki
中科院分区：
文献类型：
--
作者：
Shimokawa Tokuro;Takano Ken'ichi;Honda Zentaro;Okutani Akira;Hagiwara Masayuki
研究了具有三个交换作用的自旋1/2蜂窝晶格反铁磁体(AF)海森堡模型的基态相图，该模型是在扭曲的蜂窝晶格反铁磁体中实现的。我们特别小心地重新测量了它的多晶样品的磁化率，并通过与基于量子蒙特卡罗(QMC)方法的数值结果的比较，确定了该材料的交换参数。QMC方法还提供了平面内的基态相图。相图由一个小相和围绕该相的间隙量子顺磁相组成。后者包括六个区域的六角单线态和二聚体单线态，它们交替地无边界地闭合自旋能隙。我们进一步用QMC方法计算了各相的等时自旋结构因子。用精确对角化方法计算的自旋动力学在AF相附近和在AF相中都是连续的。具有强六方单线态关联的四个特征能带结构为将来的中子散射测量阐明基态提供了信息。
We investigate the ground-state phase diagram of a spin-1/2 honeycomb-lattice antiferromagnetic (AF) Heisenberg model with three exchange interactions,, and, that is realized in a distorted honeycomb-lattice antiferromagnet. We remeasured the magnetic susceptibility of its polycrystalline sample with special care and determined the exchange parameters of this material through the comparison with numerical results based on a quantum Monte Carlo (QMC) method. The QMC method also provides a ground-state phase diagram in theplane. The phase diagram consists of a smallphase and a gapped quantum paramagnetic phase surrounding thephase. The latter includes six regimes of hexagonal-singlet-type states and dimer-singlet-type states alternatingly without boundaries closing the spin gap. We further calculate the equal-time spin structure factor in each phase using the QMC method. The computed spin dynamics by the exact diagonalization method exhibits continua near and in the AF phase. Characteristic four energy band structures in the state with strong hexagonal-singlet-type correlations are informative to clarify the ground state ofby future neutron scattering measurements.