Spin- 12 kagome XXZ model in a field: Competition between lattice nematic and solid orders
Spin- 12 kagome XXZ model in a field: Competition between lattice nematic and solid orders
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Spin- 12 kagome XXZ 模型在一个领域：晶格向列和固体顺序之间的竞争
DOI：
10.1103/physrevb.94.235146
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发表时间：
2016
影响因子：
3.7
通讯作者：
D. Poilblanc
中科院分区：
文献类型：
--
作者：
A. Kshetrimayum;T. Picot;R. Orus;D. Poilblanc
本文数值研究了无限kagome格点上自旋为1/2的XXZ模型。为此，我们使用了基于无限投射纠缠对态（iPEPS）的不同算法，即（i）一种使用单纯形张量和9位晶胞的方法，以及（ii）一种基于粗粒化kagome晶格中的三个自旋并将其映射到具有局部和最近邻相互作用的正方形晶格模型的方法，其中通常的PEPS张量为6位和12位晶胞。与我们之前在SU（2）对称点（海森堡汉密尔顿量）的计算类似，对于从伊辛极限到XY极限的任何各向异性，我们还观察到磁化平台的出现作为磁场的函数，使用6-、9-和12位PEPS单元格，以及使用9位PEPS单元格，后者的设置能够适应固体有序。我们还发现，在，（晶格）的？和VBC阶状态的退化的九位单纯形方法的精度内，所有的各向异性。6位和12位粗粒度PEPS方法产生几乎退化的VBC和VBC-固体有序。我们还发现，在我们的准确度范围内，六位点粗粒度PEPS方法给出的能量略低，这可以通过这种方法可以处理更大量的纠缠来解释，即使在PEPS单元格不相称的情况下也是如此。与预期的基态单元格。此外，我们没有观察到手性自旋液体行为在XY点和接近XY点，最近提出的。我们的研究结果是第一张量网络调查的XXZ模型在一个领域，并揭示了附近的磁序之间的微妙竞争的数值模拟挫折量子反铁磁体，以及微妙的相互作用之间的能量优化和对称性张量网络数值模拟。
We study numerically the spin-1/2 XXZ model in a field on an infinite kagome lattice. We use different algorithms based on infinite projected entangled pair states (iPEPSs) for this, namely, (i) an approach with simplex tensors and a 9-site unit cell, and (ii) an approach based on coarse-graining three spins in the kagome lattice and mapping it to a square-lattice model with local and nearest-neighbor interactions, with the usual PEPS tensors, 6- and 12-site unit cells. Similarly to our previous calculation at the SU(2)-symmetric point (Heisenberg Hamiltonian), for any anisotropy from the Ising limit to the XY limit, we also observe the emergence of magnetization plateaus as a function of the magnetic field, atusing 6-, 9-, and 12-site PEPS unit cells, and at, andusing a 9-site PEPS unit cell, the latter setup being able to accommodatesolid order. We also find that, at, (lattice) nematic andVBC-order states are degenerate within the accuracy of the nine-site simplex method, for all anisotropy. The 6- and 12-site coarse-grained PEPS methods produce almost-degenerate nematic andVBC-solid orders. We also find that, within our accuracy, the six-site coarse-grained PEPS method gives slightly lower energies, which can be explained by the larger amount of entanglement this approach can handle, even in cases where the PEPS unit cell is not commensurate with the expected ground-state unit cell. Furthermore, we do not observe chiral spin liquid behaviors at and close to the XY point, as has been recently proposed. Our results are the first tensor network investigations of the XXZ model in a field and reveal the subtle competition between nearby magnetic orders in numerical simulations of frustrated quantum antiferromagnets, as well as the delicate interplay between energy optimization and symmetry in tensor network numerical simulations.
DOI：
10.1007/978-3-642-10449-7
发表时间：
2012-01
期刊：
Lecture Notes in Physics
影响因子：
--
作者：
D. Cabra;A. Honecker;P. Pujol
通讯作者：
D. Cabra;A. Honecker;P. Pujol