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arXiv · 1008.2654

Self-Similar Modes of Coherent Diffusion

O. Firstenberg·P. London·D. Yankelev·R. Pugatch·M. Shuker·N. Davidson
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Abstract

Self-similar solutions of the coherent diffusion equation are derived and measured. The set of real similarity solutions is generalized by the introduction of a nonuniform phase surface, based on the elegant Gaussian modes of optical diffraction. In an experiment of light storage in a gas of diffusing atoms, a complex initial condition is imprinted, and its diffusion dynamics is monitored. The self-similarity of both the amplitude and the phase pattern is demonstrated, and an algebraic decay associated with the mode order is measured. Notably, as opposed to a regular diffusion spreading, a self-similar contraction of a special subset of the solutions is predicted and observed.

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O. Firstenberg, P. London, D. Yankelev, R. Pugatch, M. Shuker, N. Davidson. 2010-08-16. Self-Similar Modes of Coherent Diffusion. https://doi.org/10.1103/physrevlett.105.183602

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