Magic transition in monitored free fermion dynamics

• URL: http://arxiv.org/abs/2507.10688v1
• Date: Mon, 14 Jul 2025 18:04:25 GMT
• Title: Magic transition in monitored free fermion dynamics
• Authors: Cheng Wang, Zhi-Cheng Yang, Tianci Zhou, Xiao Chen,
• Abstract summary: We investigate magic and its connection to entanglement in 1+1 dimensional random free fermion circuits.<n>To quantify magic, we use the Stabilizer R'enyi Entropy (SRE), which we compute numerically via a perfect sampling algorithm.<n>We show that although the SRE remains extensive as the system transitions from a critical phase to an area-law (disentangled) phase, the structure of magic itself undergoes a delocalization phase transition.
• Score: 11.25698763510275
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We investigate magic and its connection to entanglement in 1+1 dimensional random free fermion circuits, with a focus on hybrid free fermion dynamics that can exhibit an entanglement phase transition. To quantify magic, we use the Stabilizer R\'enyi Entropy (SRE), which we compute numerically via a perfect sampling algorithm. We show that although the SRE remains extensive as the system transitions from a critical phase to an area-law (disentangled) phase, the structure of magic itself undergoes a delocalization phase transition. This transition is characterized using the bipartite stabilizer mutual information, which exhibits the same scaling behavior as entanglement entropy: logarithmic scaling in the critical phase and a finite constant in the area-law phase. Additionally, we explore the dynamics of SRE. While the total SRE becomes extensive in $O(1)$ time, we find that in the critical phase, the relaxation time to the steady-state value is parameterically longer than that in generic random circuits. The relaxation follows a universal form, with a relaxation time that grows linearly with the system size, providing further evidence for the critical nature of the phase.

Related papers

• Information scrambling and entanglement dynamics in Floquet Time Crystals [49.1574468325115]
  We study the dynamics of out-of-time-ordered correlators (OTOCs) and entanglement of entropy as measures of information propagation in disordered systems.
  arXiv  Detail & Related papers  (2024-11-20T17:18:42Z)
• Measurement-induced transitions for interacting fermions [43.04146484262759]
  We develop a field-theoretical framework that provides a unified approach to observables characterizing entanglement and charge fluctuations.<n>Within this framework, we derive a replicated Keldysh non-linear sigma model (NLSM)<n>By using the renormalization-group approach for the NLSM, we determine the phase diagram and the scaling of physical observables.
  arXiv  Detail & Related papers  (2024-10-09T18:00:08Z)
• State Dependent Spread Complexity Dynamics in Many-Body Localization Transition [0.0]
  We characterize the Many-Body Localization (MBL) phase transition using the dynamics of spread complexity and inverse participation ratio in the Krylov space. Our work sheds light on the efficacy of Krylov space dynamics in understanding phase transitions in quantum many-body systems.
  arXiv  Detail & Related papers  (2024-09-03T18:00:11Z)
• Measurement induced criticality in quasiperiodic modulated random hybrid circuits [0.0]
  We study one-dimensional hybrid quantum circuits perturbed by quenched quasiperiodic (QP) modulations across the measurement-induced phase transition (MIPT) We numerically determine the associated critical properties, including the correlation length exponent consistent with saturating the Luck bound, and a universal activated dynamical scaling with activation exponent $psi cong beta$.
  arXiv  Detail & Related papers  (2023-08-07T18:00:08Z)
• Entanglement dynamics in U(1) symmetric hybrid quantum automaton circuits [3.6320095921016264]
  We study the entanglement dynamics of quantum automaton (QA) circuits in the presence of U(1) symmetry. Thanks to the special feature of QA circuits, we understand the entanglement dynamics in terms of a classical bit string model.
  arXiv  Detail & Related papers  (2023-05-29T15:09:40Z)
• The Sub-Exponential Critical Slowing Down at Floquet Time Crystal Phase Transition [4.353446104859767]
  We study critical dynamics near the Floquet time crystal phase transition. Its critical behavior is described by introducing a space-time coarse grained correlation function. We show the relaxation time has a universal sub-exponential scaling near the critical point.
  arXiv  Detail & Related papers  (2023-01-17T13:28:32Z)
• Indication of critical scaling in time during the relaxation of an open quantum system [34.82692226532414]
  Phase transitions correspond to the singular behavior of physical systems in response to continuous control parameters like temperature or external fields. Near continuous phase transitions, associated with the divergence of a correlation length, universal power-law scaling behavior with critical exponents independent of microscopic system details is found.
  arXiv  Detail & Related papers  (2022-08-10T05:59:14Z)
• Clean two-dimensional Floquet time-crystal [68.8204255655161]
  We consider the two-dimensional quantum Ising model, in absence of disorder, subject to periodic imperfect global spin flips. We show by a combination of exact diagonalization and tensor-network methods that the system can sustain a spontaneously broken discrete time-translation symmetry. We observe a non-perturbative change in the decay rate of the order parameter, which is related to the long-lived stability of the magnetic domains in 2D.
  arXiv  Detail & Related papers  (2022-05-10T13:04:43Z)
• Topological transitions with continuously monitored free fermions [68.8204255655161]
  We show the presence of a topological phase transition that is of a different universality class than that observed in stroboscopic projective circuits. We find that this entanglement transition is well identified by a combination of the bipartite entanglement entropy and the topological entanglement entropy.
  arXiv  Detail & Related papers  (2021-12-17T22:01:54Z)
• Superradiant phase transition in complex networks [62.997667081978825]
  We consider a superradiant phase transition problem for the Dicke-Ising model. We examine regular, random, and scale-free network structures.
  arXiv  Detail & Related papers  (2020-12-05T17:40:53Z)
• Universality of entanglement transitions from stroboscopic to continuous measurements [68.8204255655161]
  We show that the entanglement transition at finite coupling persists if the continuously measured system is randomly nonintegrable. This provides a bridge between a wide range of experimental settings and the wealth of knowledge accumulated for the latter systems.
  arXiv  Detail & Related papers  (2020-05-04T21:45:59Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.