Eigenstate thermalization within isolated spin-chain systems.

  title={Eigenstate thermalization within isolated spin-chain systems.},
  author={Robin Steinigeweg and J. Herbrych and P. Prelov{\vs}ek},
  journal={Physical review. E, Statistical, nonlinear, and soft matter physics},
  volume={87 1},
The thermalization phenomenon and many-body quantum statistical properties are studied on the example of several observables in isolated spin-chain systems, both integrable and generic nonintegrable. While diagonal matrix elements for nonintegrable models comply with the eigenstate thermalization hypothesis, the integrable systems show evident deviations and similarity to properties of noninteracting many-fermion models. The finite-size scaling reveals that the crossover between the two regimes… 

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