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arXiv · 2603.24225

Large deviations and conditioned monitored quantum systems: a tensor network approach

María Cea·Marcel Cech·Federico Carollo·Igor Lesanovsky·Mari Carmen Bañuls
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Abstract

Coexistence of different dynamical phases is a hallmark of glassy dynamics. This is well-studied in classical systems where the underlying theoretical framework is that of large deviation theory. The presence of a similar phase coexistence has been suggested in monitored quantum many-body systems, but the lack of suitable methods has yet prevented a systematic large deviation analysis. Here we present a tensor network framework that allows the application of large deviation theory to large quantum systems. Building on this, we locate a series of first-order dynamical phase transitions in a monitored discrete-time many-body quantum dynamics, at the level of the trajectory space. Crucially, our approach provides access not only to large-deviation statistics but also to conditioned quantum many-body states, enabling a microscopic characterization of the dynamical phases and their coexistence.

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María Cea, Marcel Cech, Federico Carollo, Igor Lesanovsky, Mari Carmen Bañuls. 2026-03-25. Large deviations and conditioned monitored quantum systems: a tensor network approach. https://arxiv.org/abs/2603.24225

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