论文标题
在可集成和不可整合振荡器链中多体混乱中测量引起的过渡的半经典极限
Semiclassical Limit of Measurement-Induced Transition in Many-Body Chaos in Integrable and Nonintegrable Oscillator Chains
论文作者
论文摘要
我们讨论了在半经典极限下连续弱位置测量结果下耦合振荡器的可集成链和不可整合链的动力学。我们表明，在此限制下，动力学由标准的随机Langevin方程来描述，测量引起的过渡似乎是噪声和耗散引起的混乱到非核转变，类似于随机同步。在不可整合的无量子耦合振荡器的链中，我们表明，以lyapunov指数和蝴蝶速度为特征的经典的超级相关器的时间生长和弹道轻角散布被停止在噪声上或相互作用强度以下。 Lyapunov指数和蝴蝶速度都像订单参数一样起作用，在非偶然阶段消失。此外，蝴蝶速度表现出关键的有限尺寸缩放。对于可集成的模型，我们考虑了经典的TODA链，并表明Lyapunov指数随噪声强度非单调变化，在零噪声限制下消失并高于临界噪声，并在中间噪声强度下最大值。 TODA链中的蝴蝶速度显示出一种奇异的行为，接近零噪声强度的可集成极限。
We discuss the dynamics of integrable and nonintegrable chains of coupled oscillators under continuous weak position measurements in the semiclassical limit. We show that, in this limit, the dynamics is described by a standard stochastic Langevin equation, and a measurement-induced transition appears as a noise- and dissipation-induced chaotic-to-nonchaotic transition akin to stochastic synchronization. In the nonintegrable chain of anharmonically coupled oscillators, we show that the temporal growth and the ballistic light-cone spread of a classical out-of-time correlator characterized by the Lyapunov exponent and the butterfly velocity, are halted above a noise or below an interaction strength. The Lyapunov exponent and the butterfly velocity both act like order parameter, vanishing in the nonchaotic phase. In addition, the butterfly velocity exhibits a critical finite-size scaling. For the integrable model, we consider the classical Toda chain and show that the Lyapunov exponent changes nonmonotonically with the noise strength, vanishing at the zero noise limit and above a critical noise, with a maximum at an intermediate noise strength. The butterfly velocity in the Toda chain shows a singular behavior approaching the integrable limit of zero noise strength.
