The bright future of optical fibers beyond telecommunications

Nowadays optical fibers have become an integral part of life in the information age. Anyway, there are a lots of non-telecom applications for fibers, too, for example in high power generation and beam delivery for high precision applications such as the scribing of the solar cells, sensing and other fields of the physics and engineering. Researchers and engineers are still working hard to develop new optical fibers, which could outperform conventional fibers in specific fields, and to exploit the advantages offered by traditional ones for more and more innovative applications. The activity carried out during the PhD course and reported in the present thesis is set in this extremely active research field. The high power Ytterbium-doped fiber laser for industrial applications have been thoroughly studied, proposing new designs for suitable large mode area (LMA) photonic crystal fibers (PCFs). Moreover, new applications have been proposed for both hollow and solid core PCFs, which can be interesting for sensing area.