Spin transport in the XXZ model at high temperatures: Classical dynamics versus quantum S=1/2 autocorrelations

  title={Spin transport in the XXZ model at high temperatures: Classical dynamics versus quantum S=1/2 autocorrelations},
  author={Robin Steinigeweg},
  journal={arXiv: Statistical Mechanics},
  • R. Steinigeweg
  • Published 30 October 2011
  • Physics
  • arXiv: Statistical Mechanics
The transport of magnetization is analyzed for the classical Heisenberg chain at and especially above the isotropic point. To this end, the Hamiltonian equations of motion are solved numerically for initial states realizing harmonic-like magnetization profiles of small amplitude and with random phases. Above the isotropic point, the resulting dynamics is observed to be diffusive in a hydrodynamic regime starting at comparatively small times and wave lengths. In particular, hydrodynamic regime… 

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Mathematical Methods of Classical Mechanics (Springer
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