论文标题
Bose-Hubbard模型在Penrose晶格中的平均场研究
Mean-field study of the Bose-Hubbard model in Penrose lattice
论文作者
论文摘要
我们基于不均匀的平均场理论研究了penrose晶格中的Bose-Hubbard模型。由于Penrose晶格中的平均配位数为四个，因此由Mott绝缘体（MI）和Superfluid（SF）相组成的平均场相图与方格相似。然而，在SF相中，BOSE冷凝物的空间分布与平方晶格中的均匀分布显着不同。我们在MI-SF相边界附近的分布中发现了一个分形结构。分形结构的出现是penrose晶格中的准二拟合性与相变临界值之间合作效应的结果。
We examine the Bose-Hubbard model in the Penrose lattice based on inhomogeneous mean-field theory. Since averaged coordination number in the Penrose lattice is four, mean-field phase diagram consisting of the Mott insulator (MI) and superfluid (SF) phase is similar to that of the square lattice. However, the spatial distribution of Bose condensate in the SF phase is significantly different from uniform distribution in the square lattice. We find a fractal structure in its distribution near the MI-SF phase boundary. The emergence of the fractal structure is a consequence of cooperative effect between quasiperiodicity in the Penrose lattice and criticality at the phase transition.
