Exponential shortcut to measurement-induced entanglement phase transitions

Abstract

Recently discovered measurement-induced entanglement phase transitions in monitored quantum circuits provide a novel example of far-from-equilibrium quantum criticality. Here, we propose a highly efficient strategy for experimentally accessing these transitions through fluctuations. Instead of directly measuring entanglement entropy, which requires an exponential number of measurements in the subsystem size, our method provides a scalable approach to entanglement transitions in the presence of conserved quantities. In analogy to entanglement entropy and mutual information, we illustrate how bipartite and multipartite fluctuations can both be employed to analyze the measurement-induced criticality. Remarkably, the phase transition can be revealed by measuring fluctuations of only a handful of qubits.

6 pages, 4 figures

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Cited by in corpus (14)

• Symmetry restoration and quantum Mpemba effect in symmetric random circuits
• Entanglement Structure and Information Protection in Noisy Hybrid Quantum Circuits
• Noise-induced phase transitions in hybrid quantum circuits
• Measurement-induced phase transitions in monitored infinite-range interacting systems
• Charge and Entanglement Criticality in a U(1)-Symmetric Hybrid Circuit of Qubits
• Measurement-induced multipartite-entanglement regimes in collective spin systems
• Universal Stochastic Equations of Monitored Quantum Dynamics
• Phase transitions induced by standard and predetermined measurements in transmon arrays
• Probing prethermal nonergodicity through measurement outcomes of monitored quantum dynamics
• Exact, Average, and Broken Symmetries in a Simple Adaptive Monitored Circuit
• Uncovering measurement-induced entanglement via directional adaptive dynamics and incomplete information
• Noise resilience in adaptive and symmetric monitored quantum circuits
• Relaxation Critical Dynamics in Measurement-induced Phase Transitions
• Identifying Entanglement Phases with Bipartite Projected Ensembles