Supersolidity in the triangular lattice spin-1/2 XXZ model: a variational perspective.
Supersolidity in the triangular lattice spin-1/2 XXZ model: a variational perspective.
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DOI：
10.1103/physrevlett.104.015301
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发表时间：
2009-10
影响因子：
8.6
通讯作者：
D. Heidarian;A. Paramekanti
中科院分区：
文献类型：
--
作者：
D. Heidarian;A. Paramekanti
本文研究了零磁场下具有最近邻反铁磁Ising耦合J（z）> 0和无阻（J（垂直）0）动力学项的三角晶格上自旋1/2XXZ模型.通过对平均场自旋态上的长程Jastrow关联的分析，我们得到了该模型在任意J（z）和任意J符号（垂直）的大晶格上的变分相图。对于J（垂直）4.7，在良好的协议与量子Monte Carlo数据。当J（垂直）> 0时，当J（z）/J（垂直）>或= 1时，出现了一个明显的平方根（3）×平方根（3）的超固体。这两种超固体都表现出自发的密度偏离半填充。在J（z）/J（垂直）=无穷大时，这两种超固体的晶序参数几乎相同，与精确结果一致。
We study the spin-1/2 XXZ model on the triangular lattice with a nearest neighbor antiferromagnetic Ising coupling J(z) > 0 and unfrustrated (J(perpendicular) 0) kinetic terms in a zero magnetic field. Incorporating long-range Jastrow correlations over a mean-field spin state, we obtain the variational phase diagram of this model on large lattices for arbitrary J(z) and either sign of J(perpendicular). For J(perpendicular) 4.7, in excellent agreement with quantum Monte Carlo data. For J(perpendicular) > 0, a distinct square root(3) x square root(3) supersolid is found to emerge for J(z)/J(perpendicular) > or = 1. Both supersolids exhibit a spontaneous density deviation from half-filling. At J(z)/J(perpendicular) = infinity, the crystalline order parameters of these two supersolids are nearly identical, consistent with exact results.