Fractional diffusion in the multiple-trapping regime and revision of the equivalence with the continuous-time random walk.

نویسنده

  • Juan Bisquert
چکیده

We investigate the macroscopic diffusion of carriers in the multiple-trapping (MT) regime, in relation with electron transport in nanoscaled heterogeneous systems, and we describe the differences, as well as the similarities, between MT and the continuous-time random walk (CTRW). Diffusion of free carriers in MT can be expressed as a generalized continuity equation based on fractional time derivatives, while the CTRW model for diffusive transport generalizes the constitutive equation for the carrier flux.

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عنوان ژورنال:
  • Physical review letters

دوره 91 1  شماره 

صفحات  -

تاریخ انتشار 2003