论文标题
多体局部系统中测量引起的纠缠过渡
Measurement-induced entanglement transitions in many-body localized systems
论文作者
论文摘要
量子纠缠对经典性诱导环境的弹性与量子多体系统的基本方面有关。最近在测量引起的纠缠过渡的背景下研究了纠缠的动力学，稳态纠缠以关键的测量概率$ p_ {c} $以从体积law缩短到区域法。有趣的是，$ p_ {c} $的值有一个区别，具体取决于基础统一动力学拼写量子信息。对于强烈的混乱系统，$ p_ {c}> 0 $，而对于弱混沌系统，例如综合模型，$ p_ {c} = 0 $。在这项工作中，我们研究了这些测量引起的纠缠转变，该系统是基础统一动力学是多体局部（MBL）的。我们证明，MBL系统中的新兴集成性意味着根据测量基础，测量引起的过渡的性质存在质量差异，当测量基础被炒作时，$ p_ {c}> 0 $何时note $ p_ {c} = 0 $。在HAAR随机电路模型中找不到此功能，在该模型中，所有本地操作员都会及时扰乱。当过渡发生在$ p_ {c}> 0 $时，我们使用有限大小的缩放来获得关键指数$ν= 1.3（2）$，接近2+0d渗透的值。我们还发现$ z = 0.98（4）$的动态临界指数和临界时的rényi熵的对数缩放缩放，这表明在临界点处于临界点的基本形式对称性。这项工作进一步展示了测量引起的纠缠过渡的性质如何取决于基础统一动力的争夺性质。这导致了有关通过开放量子系统中的测量对纠缠量子状态的控制和模拟的进一步问题。
The resilience of quantum entanglement to a classicality-inducing environment is tied to fundamental aspects of quantum many-body systems. The dynamics of entanglement has recently been studied in the context of measurement-induced entanglement transitions, where the steady-state entanglement collapses from a volume-law to an area-law at a critical measurement probability $p_{c}$. Interestingly, there is a distinction in the value of $p_{c}$ depending on how well the underlying unitary dynamics scramble quantum information. For strongly chaotic systems, $p_{c} > 0$, whereas for weakly chaotic systems, such as integrable models, $p_{c} = 0$. In this work, we investigate these measurement-induced entanglement transitions in a system where the underlying unitary dynamics are many-body localized (MBL). We demonstrate that the emergent integrability in an MBL system implies a qualitative difference in the nature of the measurement-induced transition depending on the measurement basis, with $p_{c} > 0$ when the measurement basis is scrambled and $p_{c} = 0$ when it is not. This feature is not found in Haar-random circuit models, where all local operators are scrambled in time. When the transition occurs at $p_{c} > 0$, we use finite-size scaling to obtain the critical exponent $ν= 1.3(2)$, close to the value for 2+0D percolation. We also find a dynamical critical exponent of $z = 0.98(4)$ and logarithmic scaling of the Rényi entropies at criticality, suggesting an underlying conformal symmetry at the critical point. This work further demonstrates how the nature of the measurement-induced entanglement transition depends on the scrambling nature of the underlying unitary dynamics. This leads to further questions on the control and simulation of entangled quantum states by measurements in open quantum systems.
