Monolithic rare-earth doped sol-gel tapered rib waveguide laser

We report the design, fabrication, and characterization of a monolithic tapered rib waveguide laser made of Nd doped silica hafnia sol-gel. The laser has a 604 nm thick guiding layer. CW pumping was coupled in via a grating which also coupled out the lasing signal output, while reflection gratings supported the feedback. A lasing threshold of 20 mW and an output power of 2.45 mW were measured in a 3 cm long device.