论文标题
在开放监测的量子电路中测量引起的幂律负率
Measurement-Induced Power-Law Negativity in an Open Monitored Quantum Circuit
论文作者
论文摘要
耦合到环境的通用多体系统由于腐蚀而失去了量子纠缠，并且仅具有经典相关性而发展到混合状态。在这里，我们表明测量值可以稳定开放量子系统内的量子纠缠。具体而言，在边界上的随机单一回路中，我们在数值和分析上都发现以较小的非呈速率进行的投影测量结果导致稳定状态，并且系统内部的左右perlaw {1/3}。在随机环境中，使用分析映射到定向聚合物的统计力学模型，我们表明，由于随机测量位置，可以将幂律负缩放缩放量表理解为Kardar-Parisi-Zhang的波动。进一步提高测量速率会导致相位向区域律负阶段过渡，该阶段与受监测的随机电路中无抗性的纠缠过渡的通用性相同。
Generic many-body systems coupled to an environment lose their quantum entanglement due to decoherence and evolve to a mixed state with only classical correlations. Here, we show that measurements can stabilize quantum entanglement within open quantum systems. Specifically, in random unitary circuits with dephasing at the boundary, we find both numerically and analytically that projective measurements performed at a small nonvanishing rate results in a steady state with an $L^{1/3}$ power-law scaling entanglement negativity within the system. Using an analytical mapping to a statistical mechanics model of directed polymers in a random environment, we show that the power-law negativity scaling can be understood as Kardar-Parisi-Zhang fluctuations due to the random measurement locations. Further increasing the measurement rate leads to a phase transition into an area-law negativity phase, which is of the same universality as the entanglement transition in monitored random circuits without decoherence.
