论文标题
纠缠差距，角落和对称性破裂
Entanglement gap, corners, and symmetry breaking
论文作者
论文摘要
我们研究了二维量子球形模型（QSM）的有序阶段中最低的纠缠差距$Δξ$的有限尺寸缩放。纠缠差距为$Δξ=ω/\ sqrt {l \ ln（l）} $。这与纯对数行为形成鲜明对比的是，临界点处的$Δξ=π^2/\ ln（l）$。在有序阶段，更快的衰减反映了磁顺序的存在。我们通过分析确定常数$ω$，这取决于模型色散的低能部分和两部分的几何形状。特别是，至少对于正方形的情况，我们能够计算出$ω$的角贡献。
We investigate the finite-size scaling of the lowest entanglement gap $δξ$ in the ordered phase of the two-dimensional quantum spherical model (QSM). The entanglement gap decays as $δξ=Ω/\sqrt{L\ln(L)}$. This is in contrast with the purely logarithmic behaviour as $δξ=π^2/\ln(L)$ at the critical point. The faster decay in the ordered phase reflects the presence of magnetic order. We analytically determine the constant $Ω$, which depends on the low-energy part of the model dispersion and on the geometry of the bipartition. In particular, we are able to compute the corner contribution to $Ω$, at least for the case of a square corner.
