Antoine Boniface, Ivan Gusachenko, Kishan Dholakia and Sylvain Gigan
Optica 6(3), 274-279 (2019)
Scattering of a coherent ultrashort pulse of light by a disordered medium results in a complex spatio-temporal speckle pattern. The form of the pattern can be described by knowledge of a spectrally dependent transmission matrix which can in turn be used to shape the propagation of the pulse through the medium. We introduce a method for rapid measurement of this matrix for the entire spectrum of the pulse based on a hyperspectral imaging system that is close to two orders of magnitude faster than any approach previously reported. We demonstrate narrowband as well as spatiotemporal refocusing of a femtosecond pulse temporally stretched to several picoseconds after propagation through a multiply scattering medium. This enables new routes for multiphoton imaging and manipulation through complex media.