In‐band pumped Ti:Tm:LiNbO3 waveguide amplifier and low threshold laser

The fabrication by diffusion doping and a detailed optical investigation of a Ti:Tm:LiNbO3 waveguide amplifier and of a Fabry-Perot type Ti:Tm:LiNbO3 laser are reported. Both devices are in-band pumped by a laser diode at 1650 nm. The waveguide amplifier shows broad-band optical gain in the wavelength range 1750 nm < lambda < 1900 nm. The laser emits at 1890 nm, the longest emission wavelength of a Tm:LiNbO3 laser reported so far; also 1850 nm emission could be demonstrated. Laser threshold (1890 nm) is at 4 mW coupled pump power; the slope efficiency is similar to 13.3%. Properties and potential of both devices are analyzed by extensive modeling.