SECONDMENTS

The overall objectives of this first FUNGLASS mission were “Femtosecond laser inscription of waveguides in heavy metal oxide glasses shaped as fibers, mostly for infrared applications”.

• Achievement of femtosecond laser inscription.
• Observation of index modification.
• Waveguide injection, especially in the IR range.

The project achievements were:

• Scientific highlights and research achievements/outputs
– Demonstration of laser writing in new ribbon fibers.
– Experimental confimation of directional coupler in the 2-4.5 µm spectral range with a low-transmitting silica reference sample, which opens the future confirmation in the mid-IR designed BGG glass.

• Transfer of knowledge and Training activities (workshops…)
– Expertise transfer in the modeling of wavegiude Bragg gratings.
– Expertise transfer in waveguide injection and collection in the IR.

• Qualitative indicators of progress and success
– Start of modelling of our non-conventional waveguide Bragg gratings based on the laser-activated silver photochemistry.
– Access to refractive index change in a new oxifluoride material, still compatible with high mobilities of 5 mm/s under irradiation (maybe more).
– Partial characterization of low-transmission IR couplers in a reference silica glass, which sets the experiment for further characterization for high-transmission IR couplers in a BGG glass of interest.

Figure. (a) coupling setup of the supercontinnum source (covering the 2-4.5 µm spectral range) into the injection fiber; (b) coupling setup between the injection fiber into the fs laser structured BGG glass with double-S-bend waveguides in weak/moderate interaction by evanescent coupling.