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arXiv · 2405.08861

Measurement-induced phase transitions in systems with diffusive dynamics

Hyunsoo Ha·Akshat Pandey·Sarang Gopalakrishnan·David A. Huse
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Abstract

The competition between scrambling and projective measurements can lead to measurement-induced entanglement phase transitions (MIPT). In this work, we show that the universality class of the MIPT is drastically altered when the system is coupled to a diffusing conserved density. Specifically, we consider a 1+1d random Clifford circuit locally monitored by classically diffusing particles (``measurers''). The resulting diffusive correlations in the measurement density are a relevant perturbation to the usual space-time random MIPT critical point, producing a new universality class for this phase transition. We find ``Griffiths-like'' effects due to rare space-time regions where, e.g., the diffusive measurers have a low or high density, but these are considerably weaker than the Griffiths effects that occur with quenched randomness that produce rare spatial regions with infinite lifetime.

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Hyunsoo Ha, Akshat Pandey, Sarang Gopalakrishnan, David A. Huse. 2024-05-14. Measurement-induced phase transitions in systems with diffusive dynamics. https://doi.org/10.1103/physrevb.110.l140301

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