Thèse de Ayhan Tajalli, LCAR : octobre 2012

Titre : Generation and characterization of shaped ultrashort femtosecond pulses- Applications in spatio-temporal control of femtosecond pulses through multiply scattering medium.

=> La thèse en texte intégral

Summary : From a control perspective, this manuscript shows the ability of temporal refocusing of a broadband pulse that has been strongly distorted by a random, multiply scattering medium (i.e. the temporal analogue of the spatial speckle pattern). We demonstrate this via a spatially resolved measurement of the spectral phase of the distorted pulse followed by open-loop feedback to a pulse shaper : as a result of the linearity of the scattering process, this pre-compensation forms a spatially localized flat output spectral phase and hence a short pulse. This has already stimulated much interest in the community for diverse applications such as biological imaging and the studies of quantum optics.

Publications :

1 ) A. Tajalli, D. J. McCabe, D. R. Austin, I. A. Walmsley and B. Chatel.
- Characterization of the femtosecond speckle -field of a multiply scattering medium via spatio-spectral interferometry., J. Opt. Soc. Am. B 29, 1146-1151 (2012)

2) D. J. McCabe, A. Tajalli, D. R. Austin, P. Bondare , I. A. Walmsley, S. Gigan and B. Chatel.. - Spatio-temporal focusing of an ultrafast pulse through a multiply scattering medium., Nature. Commun. 2, 447 (2011)
3) D. J. McCabe, D. R. Austin, A. Tajalli, S. Weber, I. A. Walmsley, and B. Chatel., Space-time coupling of shaped ultrafast ultraviolet pulses from an acousto-optic programmable dispersive fi-lter., J. Opt. Soc. Am. B 28, 58-64 (2011)

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