InGaAsP/InP pump lasers for Tm-doped upconversion fiber lasers and film waveguides

Low cost and reliable pump lasers were developed for blue upconversion fiber lasers and film waveguides. The recent fabrication of Tm-doped fluorocirconate (Tm:ZBLAN) glass fiber has spurred the development of blue and red fiber lasers pumped by upconversion. The performance of CW room temperature devices demonstrated to date is reviewed with emphasis on the pump sources. Spatially coherent high-power InGaAsP/InP lasers emitting at 1140 nm and 1220 nm have been fabricated by single-step growth on non-planar InP substrate. A CW power of 150 mW was measured from 750 /spl mu/m long 2 /spl mu/m wide cavity buried stripe lasers. Stable fundamental transverse mode operation was obtained up to 120 mW emitted power. Narrow and circular beam enables efficient (60-70%) coupling of the emitted power into single mode fiber.