Continuum theory of vacancy-mediated diffusion
نویسنده
چکیده
We present and solve a continuum theory of vacancy-mediated diffusion (as evidenced, for example, in the vacancy driven motion of tracers in crystals). Results are obtained for all spatial dimensions, and reveal the strongly nongaussian nature of the tracer fluctuations. In integer dimensions, our results are in complete agreement with those from previous exact lattice calculations. We also extend our model to describe the vacancy-driven fluctuations of a slaved flux line. PACS numbers: 05.40.+j, 66.30.Jt, 74.60.Ge Typeset using REVTEX 1
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