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arXiv · 2509.15634

Measurement-Driven Transitions between Area Law Phases

Hui Yu·Jiangping Hu
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Abstract

In recent years, quantum circuits consisting of unitary gates and projective measurements have become valuable tools for stimulating or preparing quantum many-body states with non-trivial properties. Here, we introduce and examine a measurement-only circuit (the projective quantum Ising model with three-spin interactions) that involves three non-commuting projective measurements. This model features three distinct phases, separated by two critical lines. We utilize two entanglement measures (topological entanglement entropy and mutual information) to identify the phase boundaries and derive various critical exponents through scaling analysis. We establish a relationship between our model and a two-dimensional statistical model (bond percolation) within certain limits. We hope that our results will shed light on further studies using other measurement-only models.

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Hui Yu, Jiangping Hu. 2025-09-19. Measurement-Driven Transitions between Area Law Phases. https://doi.org/10.1088/1402-4896%2Fadd656

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