Time reversibility of quantum diffusion in small-world networks

  title={Time reversibility of quantum diffusion in small-world networks},
  author={Sung-Guk Han and Beom Jun Kim},
  journal={Journal of the Korean Physical Society},
We study the time-reversal dynamics of a tight-binding electron in the Watts-Strogatz (WS) small-world networks. The localized initial wave packet at time t = 0 diffuses as time proceeds until the time-reversal operation, together with the momentum perturbation of the strength η, is made at the reversal time T. The time irreversibility is measured by I = |Π(t = 2T) − Π(t = 0)|, where Π is the participation ratio gauging the extendedness of the wavefunction and for convenience, t is measured… 

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