Distributed Scheme Versus MOFPA Array on the Power Scaling of a Monolithic Fiber Laser

A couple of amplifying arrays for the power scaling of the fiber lasers under diverse pumping modes are studied. The multifiber series distributed side-pumping arrangement and the cascade amplifier chains in the form of the end-pumped master oscillator fiber power amplifier (MOFPA) scheme are investigated accordingly. Those are numerically modeled based on the propagation rate equations associated with stimulated Brillouin scattering (SBS) as well as the consideration of coupling and splicing losses for large mode area fibers. The continuous wave double-clad Yb:silica fiber laser amplifier is analyzed in various amplifying stages for several cavity lengths at forward pumping regime. Despite the distributed mode exhibits a desirable beam quality, however, it suffers a low SBS threshold. On the other hand, high output power is achieved in the MOFPA configuration far from the onset of SBS.