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arXiv · 2207.00025

Exact dynamics in dual-unitary quantum circuits with projective measurements

Pieter W. Claeys·Marius Henry·Jamie Vicary·Austen Lamacraft
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Abstract

Dual-unitary circuits have emerged as a minimal model for chaotic quantum many-body dynamics in which the dynamics of correlations and entanglement remains tractable. Simultaneously, there has been intense interest in the effect of measurements on the dynamics of quantum information in many-body systems. In this work we introduce a class of models combining dual-unitary circuits with particular projective measurements that allow the exact computation of dynamical correlations of local observables, entanglement growth, and steady-state entanglement. We identify a symmetry preventing a measurement-induced phase transition and present exact results for the intermediate critical purification phase.

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Pieter W. Claeys, Marius Henry, Jamie Vicary, Austen Lamacraft. 2022-06-30. Exact dynamics in dual-unitary quantum circuits with projective measurements. https://doi.org/10.1103/physrevresearch.4.043212

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