论文标题
在二维方形格子中的偶极玻色子的交错超流相
Staggered superfluid phases of dipolar bosons in two-dimensional square lattices
论文作者
论文摘要
我们研究了二维正方形晶格中超电压玻色子的量子基态。玻色子通过排斥的偶极相互作用和S波散射相互作用。动力学由扩展的Bose-Hubbard模型描述，包括由于偶极相互作用而引起的相关跳跃，使用具有现实参数的Wannier扩展从第二个量化的哈密顿量中找到系数。我们使用Gutzwiller Ansatz确定相图，在该制度中，相关的跳跃项的系数为负，并且由于单粒子效应而可能干扰隧道。我们表明，这种干扰产生了消失的动能的交错的超氟和超酚类相，而我们识别有限动能的参数区域，而这些相位不可压缩。我们将结果与使用Gutzwiller方法获得的相图进行了比较，并使用DMRG在一个维度中找到结果。
We study the quantum ground state of ultracold bosons in a two-dimensional square lattice. The bosons interact via the repulsive dipolar interactions and s-wave scattering. The dynamics is described by the extended Bose-Hubbard model including correlated hopping due to the dipolar interactions, the coefficients are found from the second quantized Hamiltonian using the Wannier expansion with realistic parameters. We determine the phase diagram using the Gutzwiller ansatz in the regime where the coefficients of the correlated hopping terms are negative and can interfere with the tunneling due to single-particle effects. We show that this interference gives rise to staggered superfluid and supersolid phases at vanishing kinetic energy, while we identify parameter regions at finite kinetic energy where the phases are incompressible. We compare the results with the phase diagram obtained with the cluster Gutzwiller approach and with the results found in one dimension using DMRG.
