|Sylvain GIGAN||Principal investigator|
|Giorgio Volpe (PhD)||postdoc|
|Ori Katz (PhD)||postdoc|
|David Martina (PhD)||postdoc|
|Pierre Bondareff||PhD candidate (co-supervised by S. Grésillon)|
|Daria Andreoli||PhD candidate|
|Thomas Chaigne||PhD candidate|
|Hugo Defienne||PhD candidate|
We have open positions ! We are always welcoming applications of talented and motivated postdocs, PhD students, master and bachelor students. Please contact Sylvain Gigan via email to apply !
collaborations at institut Langevin
Rémi Carminati & Romain Pierrat
Beatrice Chatel, IRSAMC, Toulouse, France
Riccardo Sapienza and Niek Van Hulst, ICFO, Barcelona, Spain
Ian Walmsley, Clarendon Laboratory, Oxford, UK
European Research Council "ERC Starting Grant" Project COMEDIA
Emergence(s) funds from the City Council of Paris
"Young Researcher" ANR grant ROCOCO
starting funds from ESPCI ParisTech, UPMC, CNRS
Multiple scattering of light, be it in skin or in a glass of milk, is usually considered an inevitable perturbation. This phenomenon seemingly destroy, via multiple scattering and interferences, all spatial and phase information on the incoming wave. From an operative point of view, multiple scattering prevent image transmission and focusing of light.
This is why is it impossible to see through a layer of paint, or a sheet of paper. These medium are said to be "opaque". For coherent light, interferences produces a seemingly random pattern called "speckle". Nonetheless, multiple scattering, even though it is a very complex phenomenon, is deterministic : it is therefore in principle reversible. Speckle is a coherent intereference process, et it is possible to control it coherently. By "shaping" or "adapting" the incident light, it is possible to control the propagation and the diffusion process.
At a more fundamental level, this project also bring a better insight on the very rich physics of wave propagation in complex material. These material is an ideal playground for theoreticians and experimenters alike, at the interface of many domains of physics, such as optics, condensed matter, acoustics, statistical physics, or chaotic systems to cite just a few. The possibility to vary continuously the various parameter, from totally disorderded structures (such as suspensions in liquids) to totally ordered (such as photonics crystals), from solid to granular to liquid, from simple scattering to resonant scattering, from absorbing to amplifying media, open many fascinating prospects to study interesting problems of physics.
More information :
(click on image below)
|Transmission matrix experiment|
see also the webpage of S. Gigan (here)
S. M. Popoff, A. Aubry, G. Lerosey, M. Fink, A. C. Boccara and S. Gigan, Exploiting the Time-Reversal Operator for Adaptive Optics, Selective Focusing, and Scattering Pattern Analysis, Phys. Rev. Lett. 107, 263901 (2011) PRL ARXIV
N. Curry, P. Bondareff, M. Leclercq, N. F. van Hulst, R. Sapienza, S. Gigan, S. Gresillon, Direct Determination of Diffusion Properties of Random Media from Speckle Contrast,Optics Letters, Vol. 36, Issue 17, pp. 3332-3334 (2011) OL ARXIV
D.J. McCabe, A. Tajalli, D.R. Austin, P. Bondareff, I.A. Walmsley, S. Gigan, B. Chatel, Spatio-temporal focussing of an ultrafast pulse through a multiply scattering medium,Nature Communications 2, 447 doi:10.1038/ncomms1434 NCOMMS ARXIV
S. M. Popoff, G. Lerosey, R. Carminati, M. Fink, A. C. Boccara, S. Gigan, "Measuring the Transmission Matrix in Optics : An Approach to the Study and Control of Light Propagation in Disordered Media", Phys. Rev. Lett. 104, 100601 (2010) PRL ARXIV