Quantum Zeno effect and the many-body entanglement transition
Quantum Zeno effect and the many-body entanglement transition
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DOI：
10.1103/physrevb.98.205136
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发表时间：
2018-11-19
影响因子：
3.7
通讯作者：
Fisher, Matthew P. A.
中科院分区：
文献类型：
--
作者：
Li, Yaodong;Chen, Xiao;Fisher, Matthew P. A.
我们介绍和探讨了一个一维的“混合”量子电路模型，包括酉门和投影测量。虽然幺正门是从随机分布中抽取的，并且在电路中均匀地起作用，但测量是在整个系统的随机位置和时间进行的。通过改变测量速率，我们可以在随机幺正电路模型的体积定律纠缠相位（无测量）和“量子芝诺相位”之间进行调谐，其中强测量抑制纠缠增长以在面积定律中饱和。对多粒子波函数的量子轨迹进行了广泛的数值模拟（利用Clifford电路访问高达512个量子比特的系统），为稳定的“弱测量相”提供了证据，该相表现出体积定律纠缠熵，其系数随着测量速率的增加而降低。我们还提出了一个连续的量子动力学相变之间的“弱测量阶段”和“量子芝诺阶段”的证据，驱动的竞争之间的纠缠倾向的幺正演化和解除纠缠的倾向的投影测量。详细的稳态和动态临界特性的量子纠缠过渡访问。
We introduce and explore a one-dimensional "hybrid" quantum circuit model consisting of both unitary gates and projective measurements. While the unitary gates are drawn from a random distribution and act uniformly in the circuit, the measurements are made at random positions and times throughout the system. By varying the measurement rate we can tune between the volume law entangled phase for the random unitary circuit model (no measurements) and a "quantum Zeno phase" where strong measurements suppress the entanglement growth to saturate in an area law. Extensive numerical simulations of the quantum trajectories of the many-particle wave functions (exploiting Clifford circuitry to access systems up to 512 qubits) provide evidence for a stable "weak measurement phase" that exhibits volume-law entanglement entropy, with a coefficient decreasing with increasing measurement rate. We also present evidence for a continuous quantum dynamical phase transition between the "weak measurement phase" and the "quantum Zeno phase," driven by a competition between the entangling tendencies of unitary evolution and the disentangling tendencies of projective measurements. Detailed steady-state and dynamic critical properties of this quantum entanglement transition are accessed.