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arXiv · 2409.05517

Measuring temporal entropies in experiments

Aleix Bou-Comas·Carlos Ramos Marimón·Jan T. Schneider·Stefano Carignano·Luca Tagliacozzo
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Abstract

We propose a novel experimental protocol to measure generalized temporal entropies in many-body quantum systems. Our approach involves using local operators as probes to characterize the out-of-equilibrium dynamics induced by a geometric double quench on a replicated system. Such protocol mimics the path-integral on the corresponding Riemann surface encoding generalized temporal entanglement. We present the results of tensor network simulations of one-dimensional systems which validate the protocol and demonstrate the experimental feasibility of measuring generalized temporal entropies, and we outline the experimental requirements for implementing these quenches using state-of-the-art quantum simulators. Therefore, our results provide a physical interpretation of the meaning of generalized temporal entropies. Furthermore, they reveal that the dynamics induced on two replicas of the Ising model in a transverse field differ qualitatively from the ones of its non-integrable extension, suggesting that generalized temporal entropies can be used as a tool for identifying different dynamical classes in quantum systems.

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Aleix Bou-Comas, Carlos Ramos Marimón, Jan T. Schneider, Stefano Carignano, Luca Tagliacozzo. 2024-09-09. Measuring temporal entropies in experiments. https://doi.org/10.1103/436b-cnh8

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