Development and investigation of high power ytterbium-doped fiber lasers operating At 1018 nm
Efunbajo, Oyewole Benjamin
Please cite this item using this persistent URLhttp://hdl.handle.net/11693/33378
The development of ytterbium-doped ber lasers (YDFL) operating around 1018 nm with two major pumping schemes are reported. The study on the developed all ber lasers were characterized based on parameters such as pump source, active ber type and output-coupling ber bragg gratings. Diode lasers operating at around 915 nm, and 976 nm were used as primary pump sources for the experiments. While several works had reported 1018 nm YDFLs using 976 nm pump sources, up until now, there were no reports of the use of 915 nm for 1018 nm YDFLs in the literature. Active ber types, based on length and doping concentration of ytterbium ions were also considered. The choice of output-coupling (OC) ber bragg gratings (FBG) were made based on laser model simulation and manufacturing feasibility. Simulations were also carried out for every tested set of implemented parameters so as to minimize undesired optical e ects such as ampli ed stimulated emission (ASE) and inadequate pump absorption. For both pump sources, high power ytterbium-doped all- ber lasers operating in the 1018 nm region with good e ciency and ampli ed stimulated emission (ASE) suppression were established. In addition, the broad absorption crosssection of ytterbium-doped glasses around 915 nm was exploited as tunable pump sources for the ber laser systems demonstrated.