Subventions et des contributions :

Subvention ou bourse octroyée s'appliquant à plus d'un exercice financier (2017-2018 à 2018-2019).

The present proposal concerns a market assessment related to the development of a source of frequency agilex000D
radiation (from UV to THz) obtained by using multi-color filamentation in an in-line setup and by spectrallyx000D
shaping a femtosecond laser beam. High power frequency agile sources of optical radiation (from the visible tox000D
the THz) are not technologically mature due to complexity and cost. The current approach in non-linear opticalx000D
interaction and generation of radiation at some controlled distance is based on splitting a laser beam in severalx000D
beams, changing the frequency of some of these beams and recombining the various beams. Precise alignment,x000D
system complexity and high stability of the multi-beam system are critical and difficult to control, which limitsx000D
the practical use in a real environment. We developed a novel approach which circumvents the currentx000D
limitations offering a way to spatially and temporally overlap two-color pulses or multi color pulses in ax000D
completely collinear geometry for the generation at long distance of tunable UV, VIS, IR and/or THz sourcex000D
via nonlinear optical interaction or photocurrent generation processes. The system developed and tested allowsx000D
an easy generation of frequency-agile radiation through programmable control of the laser spectral amplitudex000D
and phase. The optical source can be generated on a range of distances (100m - km) from a single laser beamx000D
modulated into collinear multi-pulses of different wavelengths, with a controlled temporal delay between thex000D
pulses, which are combined at a controlled distance in a multiple-color filament. The system ensures ax000D
complete insensibility to alignments, vibrations and turbulences on long distances propagation particularly inx000D
air. The number of optical components in the present device is reduced offering a robust and compact way tox000D
generate remote radiation with perfectly controlled parameters for remote sensing or spectroscopy. The stablex000D
and programmable generation of tunable Infra-red emission in the range between 2µm and 12µm and THzx000D
radiation in the 2THz to 6THz range has been demonstrated at long distances.