Cyan praseodymium waveguide laser

In this Letter we report the demonstration of the first cyan Pr-based waveguide laser, fabricated inscribing depressed-cladding waveguides in Pr:Ba(Y_0.8Lu_0.2)₂F₈ by direct femtosecond laser writing. With an optimized waveguide geometry for the monoclinic crystal matrix, we demonstrate lasing at 495 nm, observing a maximum output power of 22 mW and a maximum slope efficiency of 7% in a compact 6 mm-long laser cavity. These values are comparable with those reported in the literature for solid-state devices based on bulk crystals. Incidentally, this is also the first, to our knowledge, demonstration of a waveguide visible laser based on a monoclinic crystal matrix.