High-Power Laser Architectures

Fiber lasers are distinguished above all by their exceptional ability to handle average power, thanks to their excellent surface-to-volume ratio, which facilitates beam extraction and heat dissipation. They are thus the most efficient and robust technology for achieving several continuous kilowatts, in a compact, flexible form, and with beam quality often approaching the diffraction limit.

On the other hand, fibers are naturally unsuited for high peak power, as the concentration of light within a core measuring a few tens of micrometers quickly makes nonlinear phenomena critical: Raman scattering (SRS), Brillouin scattering (SBS), phase self-modulation, TMI, and more generally, all intensity-induced instabilities. As soon as one seeks to exceed a few hundred microjoules, these effects become limiting and necessitate specific architectural choices.

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