论文标题
带有四个位点环交换
Breathing kagome XY quantum magnet with four-site ring exchange
论文作者
论文摘要
我们研究了最近邻居（NN）交换对平面XY Spin-1/2 Ferromagnet对Kagome晶格的平面XY Spin-1/2 Ferromagnet的影响，包括其他四个位点环交换。对于均匀的NN交换，此前已显示该模型从远程有序的铁磁铁转移到Z2量子旋转液体中，借助环交换。使用量子蒙特卡罗计算，基于随机串联膨胀，我们介绍了旋转刚度，量子相图，纵向静态以及横向动态结构因子的结果。我们的结果证实了3D XY的普遍性，在有限的三聚化时也证实了统一情况的量子临界点的简单延续，从重新恢复的交换参数方面。此外，在任何修剪序列化和有序阶段，基本激发可以很好地理解在线性旋转波理论方面，而在临界线之外，在旋转液相中，我们发现了Spinon Continua的特征。
We study the impact of trimerization (breathing) of the nearest-neighbor (NN) exchange on the planar XY spin-1/2 ferromagnet on the kagome lattice, including additional four-site ring exchange. For uniform NN exchange, this model has previously been shown to transit from a long-range ordered ferromagnet into a Z2 quantum spin liquid by virtue of the ring exchange. Using quantum Monte-Carlo calculations, based on the stochastic series expansion, we present results for the spin stiffness, the quantum phase diagram, the longitudinal static, as well as the transverse dynamic structure factor. Our results corroborate 3D XY universality also at finite trimerization and suggest a simple continuation of the quantum critical point of the uniform case into a line in terms of rescaled exchange parameters. Moreover, at any trimerization and in the ordered phase the elementary excitations can be understood very well in terms of linear spin wave theory, while beyond the critical line, in the spin liquid phase we find signatures of spinon continua.
