Laser sources based on rare earth doped glasses: recent strategies

Laser sources based on rare earth doped glasses are used in material processing, medical and surgical applications, remote sensing, spectroscopy, generation of ultrafast pulses, and so on. Fiber or planar waveguide laser sources are competitive with respect to other light sources, such as ion-doped crystal and bulk glass lasers, optical parametric oscillators, semiconductor and gas lasers for their high conversion efficiency, excellent beam quality, compactness of optical cavities, good heat dissipation capability. The paper illustrates a few recent strategies followed to obtain laser sources based on rare earth doped glasses, even with reference to the host materials and the dopants employed for their construction, and the corresponding applications. An example of NIR fiber optic laser fabrication is illustrated in detail.