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arXiv · 1908.11253

Measurement-induced phase transition: A case study in the non-integrable model by density-matrix renormalization group calculations

Abstract

We study the effect of local projective measurements on the quantum quench dynamics. As a concrete example, a one-dimensional Bose-Hubbard model is simulated by the matrix product state and time-evolving block decimation. We map out a global phase diagram in terms of the measurement rate in spatial space and time domain, which demonstrates a volume-to-area law entanglement phase transition. When the measurement rate reaches the critical value, we observe a logarithmic growth of entanglement entropy as the subsystem size or evolved time increases. Moreover, we find that the probability distribution of the single-site entanglement entropy distinguishes the volume and area law phases, similar to the case of disorder-induced many-body localization. We also investigate the scaling behavior of entanglement entropy and mutual information between two separated sites, which is indicative of a single universality class and thus suggests a possible unified description of this transition.

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BibTeXRIS

Qicheng Tang, W. Zhu. 2019-08-29. Measurement-induced phase transition: A case study in the non-integrable model by density-matrix renormalization group calculations. https://doi.org/10.1103/physrevresearch.2.013022

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