Lanthanide-doped Ca3(NbGa)5O12-type disordered single crystals are promising media for high power lasers with ultrashort pulse durations. In this work, planar optical waveguides in lithium-modified Yb:Ca3(NbGa)5O12 single crystals have been fabricated by O or F room temperature irradiation using 20 MeV of energy and a fluence of 1×1015 at/cm2. The produced waveguides show 7 dark modes in the O case and 6 dark modes in the F one, monitored at λ= 632.8 nm. Light confinement is induced by a ≈ 4% drop of the refractive index at ≈ 4-4.5 µm of depth which is primary associated to electronic damage for both irradiations. The irradiation induces some crystal coloration that is largely eliminated by air annealing in the 150-300 ºC temperature range. A post implantation thermal annealing reduces the waveguide propagation losses at λ= 632.8 nm of F-implanted samples up to 1.8 dB/cm.
Rare-Earth Laser & Luminescent Materials
Lanthanide-based laser single crystals and luminiscent materials are prepared and optically characterized. Emphasis is paid in femtosecond lasers and upconverting nanoparticles for biomedical purposes.