Abstract

Cladding-pumping has enabled unsurpassed scaling of the average output power of fiber lasers. However, the relatively low pump absorption compared to core-pumped fibers creates problems for three-level fiber laser at several wavelengths. One example is Nd-doped fiber lasers at ~ 930 nm. Nonlinear degradation is another problem which can even limit the pulse energies and peak powers of pulsed fibers to lower values with cladding-pumping than with corepumping. This can be a concern for frequency-doubling in crystals such as BiB₃O₆. A large core facilitates three-level operation of cladding-pmnped fibers and also mitigates nonlinear degradation such as spectral broadening. In addition, it improves the energy storage as well as the damage threshold.

© 2007 IEEE