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arXiv · 1912.08458

Entanglement entropy growth in stochastic conformal field theory and the KPZ class

Denis Bernard·Pierre Le Doussal
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Abstract

We introduce a model of effective conformal quantum field theory in dimension $d=1+1$ coupled to stochastic noise, where Kardar-Parisi-Zhang (KPZ) class fluctuations can be observed. The analysis of the quantum dynamics of the scaling operators reduces to the study of random trajectories in a random environment, modeled by Brownian vector fields. We use recent results on random walks in random environments to calculate the time-dependent entanglement entropy of a subsystem interval, starting from a factorized state. We find that the fluctuations of the entropy in the large deviation regime are governed by the universal Tracy-Widom distribution. This enlarges the KPZ class, previously observed in random circuit models, to a family of interacting many body quantum systems.

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BibTeXRIS

Denis Bernard, Pierre Le Doussal. 2019-12-18. Entanglement entropy growth in stochastic conformal field theory and the KPZ class. https://doi.org/10.1209/0295-5075/131/10007

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