In this work, we discuss mode-locking results obtained with low-loss, ion-exchanged waveguide lasers. With Yb<sup>3+</sup>-doped phosphate glass waveguide lasers, a repetition rate of up to 15.2 GHz was achieved at a wavelength of 1047 nm with an average power of 27 mW and pulse duration of 811 fs. The gap between the waveguide and the SESAM introduced negative group velocity dispersion via the Gires Tournois Interferometer (GTI) effect which allowed the soliton mode-locking of the device. A novel quantum dot SESAM was used to mode-lock Er<sup>3+</sup>, Yb<sup>3+</sup>-doped phosphate glass waveguide lasers around 1500 nm. Picosecond pulses were achieved at a maximum repetition rate of 6.8 GHz and an average output power of 30 mW. The repetition rate was tuned by more than 1 MHz by varying the pump power.
In this work, we demonstrate 3-level laser operation in a Yb,Gd,Lu:KYW waveguide laser fabricated by combination of liquid phase epitaxy and Ar<sup>+</sup> ion beam milling. Laser emission was observed at 981 nm with an absorbed threshold power of 23 mW and a slope efficiency of 58% without the use of any mirrors. With an HR/6%T cavity, the threshold was reduced to 13 mW. The output was single mode with beam radii of 4.8 μm and 3 μm in the in-plane and out-of-plane direction respectively. Laser emission was also observed at 999.8 nm with a threshold of 8 mW by using mirrors favouring the 999.8 nm transition and forming an HR/5%T cavity.
PbSe quantum dots (QDs) were grown in high-refractive-index low-melting-temperature leadphosphate glass. QDs with various sizes ranging from 2 nm to 5.3 nm were grown by controlling the growth parameters, heat-treatment temperature and time. The corresponding room-temperature exciton absorption was tuned within the infrared region from 0.93 μm to 2.75 μm. Photoluminescence was measured for samples with absorption peaks above 0.95eV. Real time quantum dot growth was demonstrated by monitoring the evolution of exciton absorption with temperature and time duration. As a demonstration of the use of QDs in laser applications, the saturation fluence (F<sub>sat</sub>) of one of the QDs was evaluated and found to be ~2.1 μJ/cm2 at 1.2 μm.