论文标题
光学晶格中二元bose气体的地面相图中的磁相变
Magnetic Phase Transition in the Ground-State Phase Diagram of Binary Bose Gases in Optical Lattices
论文作者
论文摘要
我们通过量子蒙特卡洛模拟研究了被困在二维光学晶格中的相互作用的二元卵气体的地面相图。我们的模拟显示了从$ x-y $铁磁级到莫特绝缘阶段内的旋转绝缘子的磁相过渡，每个位置有两个颗粒，用于准平衡现场的现场间和粒子内相互作用，即$ u _ {\ u _ {\ us {\ uparrow \ uparrow \ uparrow \ downarrow \ downarrow} \ liseSim u $ $。这种3D-XY过渡的特征在于沿$ z $轴建立有限的局部磁矩，$ x-y $计划中的铁磁相关性以及Mott阶段内的逆流超流量。当减少$ u _ {\ uparrow \ downarrow}/u $时，此过渡将与莫特 - 苏福利德过渡合并并成为一阶。相对于$ u _ {\ uparrow \ downarrow}/u $参数，研究了两个过渡的合并。
We investigate the ground-state phase diagram of interacting binary Bose gases trapped in two-dimensional optical lattices by means of quantum Monte Carlo simulations. Our simulations reveal a magnetic phase transition from a $x-y$ ferromagnetic-order to a spin insulator inside the Mott insulating phase with two particles per site for quasi-balanced on-site inter- and intra-particle interactions, i.e., $U_{\uparrow \downarrow} \lesssim U$. This 3D-XY transition is characterized by the establishment of a finite local magnetic moment along the $z$-axis, ferromagnetic correlations in the $x-y$ plan and by counterflow superfluidity inside the Mott phase. When decreasing $U_{\uparrow \downarrow}/U$, this transition merges with the Mott-superfluid transition and becomes first-order. The merging of the two transitions is investigated with respect to $U_{\uparrow \downarrow}/U$ parameter.
