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arXiv · 1101.0976

Shaping speckles: spatio-temporal focussing of an ultrafast pulse through a multiply scattering medium

David J. McCabe·Ayhan Tajalli·Dane R. Austin·Pierre Bondareff·Ian A. Walmsley·Sylvain Gigan·Béatrice Chatel
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Abstract

The multiple scattering of coherent light is a problem of both fundamental and applied importance. In optics, phase conjugation allows spatial focussing and imaging through a multiply scattering medium; however, temporal control is nonetheless elusive, and multiple scattering remains a challenge for femtosecond science. Here, we report on the spatially and temporally resolved measurement of a speckle field produced by the propagation of an ultrafast optical pulse through a thick strongly scattering medium. Using spectral pulse shaping, we demonstrate the spatially localized temporal recompression of the output speckle to the Fourier-limit duration, offering an optical analogue to time-reversal experiments in the acoustic regime. This approach shows that a multiply scattering medium can be put to profit for light manipulation at the femtosecond scale, and has a diverse range of potential applications that includes quantum control, biological imaging and photonics.

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David J. McCabe, Ayhan Tajalli, Dane R. Austin, Pierre Bondareff, Ian A. Walmsley, Sylvain Gigan, Béatrice Chatel. 2011-01-05. Shaping speckles: spatio-temporal focussing of an ultrafast pulse through a multiply scattering medium. https://doi.org/10.1038/ncomms1434

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