Anomalous spin transport in integrable random quantum circuits
- URL: http://arxiv.org/abs/2602.09098v1
- Date: Mon, 09 Feb 2026 19:00:02 GMT
- Title: Anomalous spin transport in integrable random quantum circuits
- Authors: Songlei Wang, Chenguang Liang, Hongzheng Zhao, Zhi-Cheng Yang,
- Abstract summary: integrable quantum circuits built from inhomogeneous XXZ R-matrices.<n>We map out the spintransport phase diagram and identify ballistic, superdiffusive, and diffusive regimes.<n>We develop a generalized hydrodynamics framework adapted to time-dependent integrable circuits.
- Score: 8.584508828874597
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: High-temperature spin transport in integrable quantum spin chains exhibits a rich dynamical phase diagram, including ballistic, superdiffusive, and diffusive regimes. While integrability is known to survive in static and periodically driven systems, its fate in the complete absence of time-translation symmetry, particularly in interacting random quantum circuits, has remained unclear. Here we construct integrable random quantum circuits built from inhomogeneous XXZ R-matrices. Remarkably, integrability is preserved for arbitrary sequences of gate layers, ranging from quasiperiodic to fully random, thereby explicitly breaking both continuous and discrete time-translation symmetry. Using large-scale time-dependent density-matrix renormalization group simulations at infinite temperature and half filling, we map out the resulting spin-transport phase diagram and identify ballistic, superdiffusive, and diffusive regimes controlled by the spectral parameters of the R-matrices. The spatiotemporal structure of spin correlations within each regime depends sensitively on the inhomogeneity, exhibiting spatial asymmetry and sharp peak structures tied to near-degenerate quasiparticle velocities. To account for these findings, we develop a generalized hydrodynamics framework adapted to time-dependent integrable circuits, yielding Euler-scale predictions for correlation functions, Drude weights, and diffusion bounds. This approach identifies the quasiparticles governing transport and quantitatively captures both the scaling exponents and fine structures of the correlation profiles observed numerically. Our results demonstrate that exact Yang-Baxter integrability is compatible with stochastic quantum dynamics and establish generalized hydrodynamics as a predictive framework for transport in time-dependent integrable systems.
Related papers
- Superdiffusion and anomalous fluctuations in chiral integrable dynamics [0.0]
We study the impact of time-reversal symmetry breaking on the transport and its universal aspects in integrable chiral spin ladders.<n>Our work shows that time-reversal symmetry breaking is compatible with superdiffusion, but insufficient to stabilize the KPZ universality in integrable systems.
arXiv Detail & Related papers (2025-10-30T18:04:02Z) - Probing emergent prethermal dynamics and resonant melting on a programmable quantum simulator [28.28351393962583]
dynamics of isolated quantum systems following a sudden quench plays a central role in many areas of material science, high-energy physics, and quantum chemistry.<n>Here, we use a programmable neutral atom quantum simulator to explore quench dynamics in spin models with up to 180 qubits.<n>We trace their robustness to Floquet-like prethermal steady states that are stabilized over long emergent timescales.
arXiv Detail & Related papers (2025-10-13T17:58:04Z) - Quantum channel for modeling spin-motion dephasing in Rydberg chains [44.99833362998488]
We introduce a quantum channel to model the dissipative dynamics resulting from the coupling between spin and motional degrees of freedom in chains of neutral atoms with Rydberg interactions.<n>We benchmark the accuracy of our approach against exact diagonalization for small systems, identifying its regime of validity and the onset of perturbative breakdown.<n>We then apply the quantum channel to compute fidelity loss during transport of single-spin excitations across extended Rydberg chains in intractable regimes via exact diagonalization.
arXiv Detail & Related papers (2025-06-30T17:37:38Z) - Many-body quantum geometry in time-dependent quantum systems with emergent quantum field theory instantaneously [13.437981636279718]
We study many-body quantum geometric effects in time-dependent system with emergent quantum integrable field theory instantaneously.<n>Our results unveil telltale quantum geometric signatures in time-dependent many-body systems, elucidating the intricate interplay between quantum geometry and dynamics.
arXiv Detail & Related papers (2025-03-24T07:09:04Z) - Anomalous transport in U(1)-symmetric quantum circuits [41.94295877935867]
Investigation of discrete-time transport in a generic U(1)-symmetric disordered model tuned across an array of different dynamical regimes.
We develop an aggregate quantity, a circular statistical moment, which is a simple function of the magnetization profile.
From this quantity we extract transport exponents, revealing behaviors across the phase diagram consistent with localized, diffusive, and - most interestingly for a disordered system - superdiffusive regimes.
arXiv Detail & Related papers (2024-11-21T17:56:26Z) - 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) - Quantum many-body spin ratchets [0.0]
We show that breaking of space-reflection symmetry results in a drift in the dynamical spin susceptibility.<n>We also show that the scaled cumulant generating function of the time-integrated current instead obeys a generalized fluctuation relation.
arXiv Detail & Related papers (2024-06-03T17:51:36Z) - Universal stability of coherently diffusive 1D systems with respect to decoherence [0.0]
We show that transport is exceptionally stable against decoherent noise when coherent diffusion is present.
Our results might shed new light on the functionality of many biological systems, which often operate at the border between the ballistic and localized regimes.
arXiv Detail & Related papers (2023-07-11T15:49:51Z) - 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) - Emergent tracer dynamics in constrained quantum systems [0.0]
We show how the tracer motion of tagged, distinguishable particles can effectively describe transport in various homogeneous quantum many-body systems.
We consider systems of spinful particles on a one-dimensional lattice subjected to constrained spin interactions.
arXiv Detail & Related papers (2022-05-16T18:00:02Z) - Stochastic Path Integral Analysis of the Continuously Monitored Quantum
Harmonic Oscillator [0.0]
We deduce the evolution equations for position and momentum expectation values and the covariance matrix elements from the system's characteristic function.
Our results provide insights into the time dependence of the system during the measurement process, motivating their importance for quantum measurement engine/refrigerator experiments.
arXiv Detail & Related papers (2021-03-10T15:04:49Z) - 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.