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arXiv · 1901.11497

Topological transformations of speckles

Jerome Gateau·Ferdinand Claude·Gilles Tessier·Marc Guillon
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Abstract

Deterministic control of coherent random light is highly important for information transmission through complex media. However, only a few simple speckle transformations can be achieved through diffusers without prior characterization. As recently shown, spiral wavefront modulation of the impinging beam allows permuting intensity maxima and intrinsic $\pm 1$-charged optical vortices. Here, we study this cyclic-group algebra when combining spiral phase transforms of charge $n$, with $D_3$- and $D_4$-point-group symmetry star-like amplitude modulations. This combination allows statistical strengthening of permutations and controlling the period to be 3 and 4, respectively. Phase saddle-points are shown to complete the cycle. These results offer new tools to manipulate critical points in speckles.

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Jerome Gateau, Ferdinand Claude, Gilles Tessier, Marc Guillon. 2019-07-17. Topological transformations of speckles. https://doi.org/10.1364/optica.6.000914

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