Waveguide Tm: Lu₂O₃ ceramic laser fabricated by ultrafast laser inscription

Ultrafast laser inscription (ULI) allows the fabrication of compact, highly-efficient and robust laser sources over a broad range of crystalline, ceramic and glass gain media. For instance, subsurface waveguides can be formed by the stress induced refractive index modification effect which takes place between two parallel modified regions referred to as “Type II” guiding [1]. Previously, a family of laser hosts known as sesquioxides, namely Lu2O3, Sc2O3 and LuScO3, have been shown to demonstrate efficient, high-power and tunable laser operation around the 2 μm region in both continuous-wave and pulsed regimes when doped with Tm3+ [2, 3]. Combining the Tm3+-doped sesquioxide material properties with the ULI waveguide laser geometry provides a means to produce compact, low-threshold and efficient laser sources near 2 μm with the potential for high pulse repetition rate ultrafast operation. Here we report, to the best of our knowledge, the first demonstration of a ceramic Tm:Lu2O3 waveguide laser source fabricated by ULI.