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

@article{Steinigeweg2011SpinTI,
  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},
  year={2011}
}
  • 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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References

SHOWING 1-2 OF 2 REFERENCES
Finite-temperature dynamical density matrix renormalization group and the Drude weight of spin-1/2 chains.
TLDR
It is found that D is nonzero--and thus transport is dissipationless--everywhere in the gapless phase of the XXZ spin-1/2 Heisenberg chain, and an upper bound to D is established by comparing with bosonization.
Mathematical Methods of Classical Mechanics (Springer
  • 1978