Out-of-equilibrium phase diagram of the quantum random energy model

2020/09/30 by Giulio Biroli, Davide Facoetti, Marco Schirò +3
Mathematics · Physics and Astronomy · #Eigenfunction #Eigenvalues and eigenvectors #Ergodic theory #Fractal #Hilbert space #Mathematical analysis #Mathematics #Multifractal system #Opinion Dynamics and Social Influence #Phase (matter) #Phase diagram #Phase space #Physics #Pure mathematics #Quantum #Quantum many-body systems #Quantum mechanics #Statistical physics #Theoretical and Computational Physics #cond-mat.dis-nn #cond-mat.quant-gas #cond-mat.stat-mech #quant-ph

paper · pdf · doi:10.1103/physrevb.103.014204

published as Phys. Rev. B 103, 014204 (2021) · 21 pages, 13 figures

openalex publication_date 2021/01/29 · arxiv created 2021/03/12 · arxiv updated 2021/03/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

The quantum version of Derrida's Random Energy model is the simplest model of a quantum glass. Here, the authors study its dynamical phase diagram, revealing the existence of three distinct dynamical phases: a many-body fully localized phase at low energy, an ergodic phase at high energy, and a multifractal ``bad metal'' phase at intermediate energy. In the latter, eigenfunctions occupy a diverging volume, yet an exponentially vanishing fraction of the total Hilbert space.

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