论文标题
在带有耗散缺陷的费米子链中的纠缠消极情绪：确切的结果
Entanglement negativity in a fermionic chain with dissipative defects: Exact results
论文作者
论文摘要
我们研究了一个局部损失的自由屈服链中费米子对数负性的动力学，该损失充当耗散杂质。该链最初是在通用的费米海中制备的。在大型子系统和长时间的标准流体动力学极限中，其比率固定了，两个子系统之间的负态由一个简单的公式描述，这仅取决于杂质的有效吸收系数。负性在短时间内线性增长，然后饱和到体积范围缩放。从物理上讲，这反映了随着杂质部位纠缠激发对的时间的持续产生。有趣的是，与统一动力的情况相反，消极情绪与Rényi指数$ 1/2 $的Rényi共同信息不同。这反映了耗散过程和统一过程之间的相互作用。纠缠对的负含量是根据子系统有效的两态混合密度矩阵获得的。在对数校正的情况下，初始费米海的临界性反映了。对数缩放的预将因子取决于损失率，这表明耗散和关键性之间存在非平凡的相互作用。
We investigate the dynamics of the fermionic logarithmic negativity in a free-fermion chain with a localized loss, which acts as a dissipative impurity. The chain is initially prepared in a generic Fermi sea. In the standard hydrodynamic limit of large subsystems and long times, with their ratio fixed, the negativity between two subsystems is described by a simple formula, which depends only on the effective absorption coefficient of the impurity. The negativity grows linearly at short times, then saturating to a volume-law scaling. Physically, this reflects the continuous production with time of entangling pairs of excitations at the impurity site. Interestingly, the negativity is not the same as the Rényi mutual information with Rényi index $1/2$, in contrast with the case of unitary dynamics. This reflects the interplay between dissipative and unitary processes. The negativity content of the entangling pairs is obtained in terms of an effective two-state mixed density matrix for the subsystems. Criticality in the initial Fermi sea is reflected in the presence of logarithmic corrections. The prefactor of the logarithmic scaling depends on the loss rate, suggesting a nontrivial interplay between dissipation and criticality.
