Switchable single-dual-wavelength Yb,Na:CaF₂ waveguide lasers operating in continuous-wave and pulsed regimes

Depressed-cladding waveguides are produced in a Yb,Na:CaF₂ laser crystal by applying an ultrafast laser inscription. Under pumping at 946 nm, continuous-wave (CW) and Q-switched laser oscillations with low thresholds are realized in these waveguide structures. With the variation of pumping power, switchable single- and dual-wavelength laser emissions peaking at 1013.9 nm and 1027.9 nm are generated. The maximum output power achieved for CW lasing is about 170 mW, corresponding to an optical-to-optical conversion efficiency as high as 45.3%. A pulse energy of 0.13 μJ is obtained for the waveguide laser operating in the pulsed regime.