Spectroscopic characterization and laser performance of resonantly diode-pumped Er(3+)-doped disordered NaY(WO4)2

Synthesis and Laser-Related Spectroscopy of Er:Y2O3 Optical Ceramics as a Gain Medium for In-Band-Pumped 1.6 µm Lasers

In this paper, Er:Y2O3 optical ceramics were fabricated and details of the synthesis were presented. The spectral–luminescent properties of Er3+:Y2O3 optical ceramics were investigated. The absorption and emission cross-section spectra were determined. The luminescence kinetics at near 1.6 µm was single exponential and the lifetime of erbium 4I13/2 energy level was determined. In the frame of the conventional Judd–Ofelt theory, the emission properties of the energy levels of erbium 4I13/2 and 4I11/2 involved in laser operation at near 1.6 µm were calculated. The gain coefficient curves for typical values of the relative population of the upper laser level 4I13/2 were presented. The composition and structure were studied using the SEM, XRD, FTIR spectroscopy, and X-ray computer tomography techniques.

Mode-locked laser operation of Indium-modified Yb:KY(WO₄)₂ single crystal

We report the first pulsed laser operation of an Indium-modified Yb:KY(WO4)2 crystal. Indium incorporation enlarges the broadening of the Yb3+ optical bands, reduces crystal lattice parameters and increases n(p) refractive index. A KY0.8In0.07Yb0.13(WO4)2 crystal pumped at 981 nm with a Ti-sapphire laser in a SESAM modulated resonator produces at 300 K self-starting and stable mode-locking. The shortest laser pulses achieved were centred at λ = 1041.1 nm, have a duration of 96 fs with average power of 134 mW and repetition rate of 103.5 MHz (1.3 nJ/pulse).

Spectroscopic properties and laser performance of resonantly-pumped cryo-cooled Er³⁺:GdVO₄

We report a highly efficient cryo-cooled eye-safe laser operation of a resonantly-pumped (in-band) Er³⁺:GdVO₄ single crystal. The maximum continuous wave (CW) power of 10.3 W with 84% slope efficiency was achieved at 1598.7 with pumping at 1538.6 nm by a spectrally-narrowed Er-fiber laser. Under the 1529 nm resonant pumping by a commercially available diode bar stack operating in a quasi-CW (QCW) mode, the laser delivered 37 W of output power with 68% slope efficiency. This is believed to be the first reported cryo-cooled Er³⁺:GdVO₄ laser, resonantly-pumped into the ⁴I₁₅/₂ →⁴I₁₃/₂ transition.