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Updated: Sep 1, 2025
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Subdiffusive hydrodynamics of nearly integrable anisotropic spin chains
Jacopo De Nardis1, Sarang Gopalakrishnan2, Romain Vasseur3
1Laboratoire de Physique Théorique et Modélisation, CNRS UMR 8089, CY Cergy Paris Université, 95302 Cergy-Pontoise Cedex, France.
Summary
Spin transport in Heisenberg spin chains exhibits subdiffusive behavior (z=4) due to perturbations. Diffusion is eventually recovered, with a constant independent of perturbation strength, determined by anisotropy.
Area of Science:
- Condensed Matter Physics
- Quantum Spin Dynamics
Background:
- Heisenberg spin chains are fundamental models for magnetism.
- Integrability-breaking perturbations can drastically alter spin transport properties.
Purpose of the Study:
- To investigate spin transport in easy-axis Heisenberg spin chains under integrability-breaking perturbations.
- To characterize the nature of spin transport (diffusive vs. subdiffusive) and its dependence on perturbation strength and anisotropy.
Main Methods:
- Theoretical analysis of spin transport in perturbed Heisenberg spin chains.
- Numerical simulations to provide evidence for theoretical predictions.
- Analysis of quasiparticle dynamics and effective constraints.
Main Results:
- Subdiffusive spin transport with a dynamical exponent z=4 is observed up to long timescales.
- For infinite anisotropy, transport remains subdiffusive at all times.
- For finite anisotropy, diffusion is recovered at late times, with a diffusion constant independent of perturbation strength and solely dependent on anisotropy.
Conclusions:
- The diffusion constant in near-integrable diffusive spin chains is generally not perturbative with respect to integrability-breaking strength.
- Dynamical screening of quasiparticle excitations and effective dynamical constraints govern the observed transport behavior.
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