论文标题
零温度超导体 - 边缘金属 - $ 2D $骨系统中的绝缘体过渡
Zero temperature superconductor - edge metal - insulator transition in $2D$ bosonic systems
论文作者
论文摘要
由于最近在$ t = 0 $的二维超导体 - 绝缘体跃迁中对中间骨金属状态的实验观察到的动机，我们研究了一个扩展的玻色哈伯德模型，每个位置的大量粒子限制。除了两个耦合$ xy $型号方面，我们还发现除了绝缘阶段和$（2+1）d $ superfluid阶段（另外两个阶段）之外，我们还会发现。一个阶段是$ 2D $超级流体阶段，该阶段从$（2+1）d $到$ 2D $的交叉阶段是由于初期费用订购而发生的，该订购由$θ$无序发出信号，并且与超olid阶段密切相关。另一个新阶段是边缘金属状态，其特征是零超氟刚度，零电荷排序和零体积可压缩性。但是，系统的边缘可压缩性为非零。虽然我们没有找到任何具有$ 2D $金属电导率的中间状态，但我们能够将这些结果连接到$ \ mathrm {mos_2} $上的STM实验，显示了整个$ 2D $ $ $ $ \ MATHRM {MOS_2} $ samples的整个边缘的有限状态密度。
Motivated by the recent experimental observation of an intermediate bosonic metallic state in the two-dimensional superconductor-insulator transition at $T=0$, we study an extended Bose Hubbard model in the limit of large number of particles per site. Using a representation of this in terms of two coupled $XY$ models, we find, in addition to an insulating phase and a $(2+1)D$ superfluid phase, two other phases. One phase is a $2D$ superfluid phase where a crossover from $(2+1)D$ to $2D$ has taken place as a result of incipient charge ordering, signaled by $θ$ disordering, and which is closely related to a supersolid phase. The other new phase is an edge metal state characterized by zero superfluid stiffness, zero charge ordering, and zero bulk compressibility. However, the edge compressibility of the system is nonzero. While we do not find any intermediate state with $2D$ metallic conductivity, we are able to connect these results to STM experiments on $\mathrm{MoS_2}$ showing brims of finite density of states around the entire edge of $2D$ $\mathrm{MoS_2}$ samples.
