1. Introduction to fiber laser sources

Before getting into the details, it is important to provide an overview of the performance of fiber lasers and the reasons for their success. The average power obtained in a diffraction-limited beam can reach several kilowatts in continuous operation. This impressive average power is due in part to the geometry of the optical fiber, which acts as a very good heat sink due to the large ratio between the surface area in contact with the outside and the total volume. This power reaches over 100 kW for systems with less than perfect beam quality.

Fiber optic sources also enable the generation of optical pulses. Whether in nanosecond or femtosecond pulse mode, the average power generated reaches several hundred watts, and the energy limit per pulse is a few millijoules. These performances are generally achieved using ytterbium-doped fibers. Fiber lasers enable the generation...