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How to Measure Subdiffusion Parameters

T. Kosztolowicz·K. Dworecki·St. Mrowczynski
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Abstract

We propose a method to measure the subdiffusion parameter $α$ and subdiffusion coefficient $D_α$ which are defined by means of the relation $ =\frac{2D_α} {Γ(1+α)} t^α$ where $ $ denotes a mean square displacement of a random walker starting from $x=0$ at the initial time $t=0$. The method exploits a membrane system where a substance of interest is transported in a solvent from one vessel to another across a thin membrane which plays here only an auxiliary role. We experimentally study a diffusion of glucose and sucrose in a gel solvent, and we precisely determine the parameters $α$ and $D_α$, using a fully analytic solution of the fractional subdiffusion equation.

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BibTeXRIS

T. Kosztolowicz, K. Dworecki, St. Mrowczynski. 2005-04-11. How to Measure Subdiffusion Parameters. https://doi.org/10.1103/physrevlett.94.170602

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