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Diffusion in a Random Velocity Field: Spectral Properties of a Non-Hermitian Fokker-Planck Operator

J. T. Chalker·Z. Jane Wang
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Abstract

We study spectral properties of the Fokker-Planck operator that describes particles diffusing in a quenched random velocity field. This random operator is non-Hermitian and has eigenvalues occupying a finite area in the complex plane. We calculate the eigenvalue density and averaged one-particle Green's function, for weak disorder and dimension d>2. We relate our results to the time-evolution of particle density, and compare them with numerical simulations.

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J. T. Chalker, Z. Jane Wang. 1997-04-23. Diffusion in a Random Velocity Field: Spectral Properties of a Non-Hermitian Fokker-Planck Operator. https://doi.org/10.1103/physrevlett.79.1797

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