AI 中文总结
研究(1 + 1)维共形场论中边界条件突变的局部量子猝灭，推导半直线一点函数时间演化表达式，通过与模拟对比揭示边界猝灭动力学特征及非平衡纠缠动力学与边界临界现象的联系。
AI 中文摘要
我们研究了一类局部量子猝灭，其中(1 + 1)维共形场论的共形边界条件突然改变。我们推导了半直线上一点函数时间演化的一个非常简单且通用的表达式。该结果直接描述了猝灭产生的扰动的传播，进而使我们能够确定与边界相邻子系统的二分纠缠动力学。我们表明，一旦子系统与猝灭事件完全因果连接，纠缠熵会经历一个急剧的有限跳跃，其大小由与初始和最终边界条件相关的边界g因子之比的对数普遍给出。我们将这些分析预测与临界伊辛自旋链的矩阵乘积态模拟进行对比，发现高度吻合。数值分析还使我们能够研究自旋翻转纠缠不对称性的时间演化，揭示从边界发出的对称破缺扰动如何在系统中传播。我们的结果揭示了边界猝灭的普遍动力学特征，并建立了非平衡纠缠动力学与边界临界现象之间的直接联系。
英文摘要
We investigate a class of local quantum quenches in which the conformal boundary condition of a (1+1)-dimensional conformal field theory is abruptly changed. We derive a remarkably simple and universal expression for the time evolution of one-point functions on the half-line. This result provides a direct description of the propagation of the disturbance generated by the quench and, in turn, allows us to determine the dynamics of bipartite entanglement for subsystems adjacent to the boundary. We show that, once the subsystem becomes fully causally connected to the quench event, the entanglement entropy undergoes a sharp finite jump whose magnitude is universally given by the logarithm of the ratio of the boundary g-factors associated with the initial and final boundary conditions. We benchmark these analytical predictions against Matrix Product State simulations of the critical Ising spin chain, finding excellent agreement. The numerical analysis further allows us to investigate the time evolution of the spin-flip entanglement asymmetry, revealing how the symmetry-breaking perturbation emitted from the boundary propagates through the system. Our results uncover universal dynamical signatures of boundary quenches and establish a direct connection between nonequilibrium entanglement dynamics and boundary critical phenomena.
Comments20 pages, 6 figures
