Broadband submicron flattened dispersion compensating fiber with asymmetrical fluoride doped core

Dispersion Compensating Fibres for Fibre Optic Telecommunication Systems

“…Material and structural parameters are key features in order to obtain exact CD at each λ, but the accuracy and quality of production could become a critical issue, especially in submicron fibres whose small holes with the diameter being less than one micron is problematic for some manufacturing technologies. All this combined with the application of new materials that should be processed in different way compared to siliceous materials could result in both attenuation and CD properties far from the expectations [32].…”

“…They could be enhanced by very careful optimizing the material composition. For example fluorides could be used as additives, but they could also be used as a background material instead of silicon dioxide, which could be evaluated as significant progress in the field [32]. The fluorides have low effective index, broad range of λs and low attenuation.…”

“…The fluorides have low effective index, broad range of λs and low attenuation. One could consider the use of BaF 2 , CaF 2 and more advanced ZBGA (ZrF 4 -BaF 2 -GdF 3 -AlF 3 ) or ZBLAN (ZrF 4 -BaF 2 -LaF 3 -AlF 3 -NaF) [32]. In addition, because those materials are composite, it is possible to change their composition in a compound in order to obtain ne ff value or its slope in the investigated area of λ.…”

“…For example, the core doped by using germanium dioxide would exhibit the n eff of about 1.48 and concurrently the cladding index doped by using F-SiO 2 would exhibit the index of about 1.43. Similar solution (in general modified W-type index profile fibre) could be employed in systems with WDM [32], [34].…”

“…The theoretical attenuation could even be of 0.01 dB/km, in the range from 0.3 µm to 4.3 µm. The n eff in telecom band is 1.47 -1.52 [32,36].…”