Finite-temperature phase diagram of hard-core bosons in two dimensions.
Finite-temperature phase diagram of hard-core bosons in two dimensions.
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DOI：
10.1103/physrevlett.88.167208
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发表时间：
2001-10
影响因子：
8.6
通讯作者：
G. Schmid;S. Todo;M. Troyer;A. Dorneich
中科院分区：
文献类型：
--
作者：
G. Schmid;S. Todo;M. Troyer;A. Dorneich
利用量子蒙特卡罗方法计算了具有最近邻排斥的正方晶格硬核玻色子Hubbard模型的有限温度相图。该模型等价于磁场中的各向异性自旋1/2XXZ模型。我们提出的丰富的相图与一个一级之间的过渡的固体和超流相，而不是以前的超固体和三临界点相分离。不寻常的重入行为与订购时，发现温度升高，类似的Pomeranchuk效应在3 He。
We determine the finite-temperature phase diagram of the square lattice hard-core boson Hubbard model with nearest neighbor repulsion using quantum Monte Carlo simulations. This model is equivalent to an anisotropic spin-1/2 XXZ model in a magnetic field. We present the rich phase diagram with a first order transition between a solid and superfluid phase, instead of a previously conjectured supersolid and a tricritical end point to phase separation. Unusual reentrant behavior with ordering upon increasing the temperature is found, similar to the Pomeranchuk effect in 3He.