The engineering effort to push a laser design to higher output powers without changing its fundamental operating principles or ruining its beam profile. In fiber lasers and solid-state systems, power scaling is usually limited by thermal effects, such as thermal lensing, stress fracture, or the onset of nonlinear effects like SBS and SRS.
We hit a wall with the power scaling on this amplifier because stimulated Brillouin scattering kicks in above two kilowatts.
Power scaling is rarely as simple as pumping harder; it almost always involves managing the heat that ruins beam quality.
Related terms
Thermal lensing
The lens effect a heated gain medium or optic creates as its center gets hotter than its edges.
SBS
Stimulated Brillouin Scattering: narrow-linewidth light scattering backward off sound waves it creates in fiber.
Fiber laser
A laser whose gain medium is an optical fiber with a rare-earth-doped core, pumped by diodes.
Slope efficiency
The rate at which laser output power rises per unit of extra pump power above threshold.