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Measuring temporal entropies in experiments

Aleix Bou-Comas1, Carlos Ramos Marimón2, Jan T. Schneider1, Stefano Carignano3, and Luca Tagliacozzo1,*

  • *Contact author: luca.tagliacozzo@iff.csic.es
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Phys. Rev. Research 8, 023229 – Published 1 June, 2026

DOI: https://doi.org/10.1103/436b-cnh8

Abstract

We propose an 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 that 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 those of its nonintegrable extension, suggesting that generalized temporal entropies can be used as a tool for identifying different dynamical classes in quantum systems.

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Phys. Rev. Research 8, 023229– Published 1 June, 2026
  • Received 25 November 2024
  • Accepted 19 April 2026
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