论文标题
非均匀间距的非线性纠缠增长
Nonlinear entanglement growth in inhomogeneous spacetimes
论文作者
论文摘要
纠缠已成为表征量子物质的核心,无论是在平衡中还是在平衡中。在动态环境中,纠缠在通用系统中表现出通用的线性时间生长,这源于平面几何形状中的基础线性光锥。但是,不均匀的空间可能导致强烈弯曲的轨迹。尽管这样的弯曲轨迹在关键影响相关性扩散并因此是轻锥结构的情况下,但它仍然难以捉摸,这如何影响纠缠动态。在这项工作中,我们研究了淬灭后一维量子系统中纠缠熵的实时演变,这改变了哈密顿量的基本时空背景。具体而言,我们专注于Rindler空间,描述了与黑洞相近的时空。作为主要结果,我们发现纠缠以一种通用方式与互动和非相互作用的量子物质增长。我们进一步观察到,与平面Minkowski空间的代数相反,渐近放松变为指数,并且在黑洞附近,大型子系统的放松时间与子系统大小无关。我们研究纠缠动力学,包括非相互作用的费米子,允许精确的数值解决方案,以及代表范式类别的ergodic系统类别的随机单位电路。
Entanglement has become central for the characterization of quantum matter both in and out of equilibrium. In a dynamical context entanglement exhibits universal linear temporal growth in generic systems, which stems from the underlying linear light cones as they occur in planar geometries. Inhomogeneous spacetimes can lead, however, to strongly bent trajectories. While such bent trajectories crucially impact correlation spreading and therefore the light-cone structure, it has remained elusive how this influences the entanglement dynamics. In this work we investigate the real-time evolution of the entanglement entropy in one-dimensional quantum systems after quenches which change the underlying spacetime background of the Hamiltonian. Concretely, we focus on the Rindler space describing the spacetime in close vicinity to a black hole. As a main result we find that entanglement grows sublinearly in a generic fashion both for interacting and noninteracting quantum matter. We further observe that the asymptotic relaxation becomes exponential, as opposed to algebraic for planar Minkowski spacetimes, and that in the vicinity of the black hole the relaxation time for large subsystems becomes independent of the subsystem size. We study entanglement dynamics both for the case of noninteracting fermions, allowing for exact numerical solutions, and for random unitary circuits representing a paradigmatic class of ergodic systems.