Entanglement dynamics and Page curves in random permutation circuits

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Szász-Schagrin, Dávid, Mazzoni, Michele, Bertini, Bruno, Klobas, Katja, Piroli, Lorenzo
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866915868899803136
author Szász-Schagrin, Dávid
Mazzoni, Michele
Bertini, Bruno
Klobas, Katja
Piroli, Lorenzo
author_facet Szász-Schagrin, Dávid
Mazzoni, Michele
Bertini, Bruno
Klobas, Katja
Piroli, Lorenzo
contents The characterization of ensembles of many-qubit random states and their realization via quantum circuits are crucial tasks in quantum-information theory. In this work, we study the ensembles generated by quantum circuits that randomly permute the computational basis, thus acting classically on the corresponding states. We focus on the averaged entanglement and present two main results. First, we derive generically tight upper bounds on the entanglement that can be generated by applying permutation circuits to arbitrary initial states. We show that the late-time ``entanglement Page curves'' are bounded in terms of the initial state participation entropies and its overlap with the ``maximally antilocalized'' state. Second, comparing the averaged Rényi-$2$ entropies generated by $(i)$ an infinitely deep random circuit of two-qubit gates and $(ii)$ global random permutations, we show that the two quantities are different for finite $N$ but the corresponding Page curves coincide in the thermodynamic limit. We also discuss how these conclusions are modified by additional random phases or considering circuits of $k$-local gates with $k\geq 3$. Our results are exact and highlight the implications of classical features on entanglement generation in many-body systems.
format Preprint
id arxiv_https___arxiv_org_abs_2505_06158
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Entanglement dynamics and Page curves in random permutation circuits
Szász-Schagrin, Dávid
Mazzoni, Michele
Bertini, Bruno
Klobas, Katja
Piroli, Lorenzo
Statistical Mechanics
Quantum Physics
The characterization of ensembles of many-qubit random states and their realization via quantum circuits are crucial tasks in quantum-information theory. In this work, we study the ensembles generated by quantum circuits that randomly permute the computational basis, thus acting classically on the corresponding states. We focus on the averaged entanglement and present two main results. First, we derive generically tight upper bounds on the entanglement that can be generated by applying permutation circuits to arbitrary initial states. We show that the late-time ``entanglement Page curves'' are bounded in terms of the initial state participation entropies and its overlap with the ``maximally antilocalized'' state. Second, comparing the averaged Rényi-$2$ entropies generated by $(i)$ an infinitely deep random circuit of two-qubit gates and $(ii)$ global random permutations, we show that the two quantities are different for finite $N$ but the corresponding Page curves coincide in the thermodynamic limit. We also discuss how these conclusions are modified by additional random phases or considering circuits of $k$-local gates with $k\geq 3$. Our results are exact and highlight the implications of classical features on entanglement generation in many-body systems.
title Entanglement dynamics and Page curves in random permutation circuits
topic Statistical Mechanics
Quantum Physics
url https://arxiv.org/abs/2505.06158