We report laser-written chip lasers with potential to be a platform planar technology versatile enough to cover the visible through to the mid-infrared spectral region. By femtosecond laser direct-writing a thulium doped fluoride based glass host (ZBLAN), we have demonstrated a 151% quantum efficiency λ=1.9 μm laser with a close to diffraction limited beam quality (M²~ 1.12 ± 0.08) with 225 nm of continuous tunability in a device that can be rapidly fabricated by singlestep optical processing. The 9 mm long planar chip developed for concept demonstration contains fifteen large modearea waveguides that can operate in semi-monolithic or external cavity laser configurations. This chip laser has achieved the highest quantum efficiency from a planar glass waveguide laser. The depressed cladding geometry supports the largest fundamental modes reported for a rare-earth doped waveguide laser thereby favouring high peak-power operation which is demonstrated by achieving 1.9 kW peak-power pulses when Q-switched.

Date Published: 6 March 2013
PDF: 8 pages
Proc. SPIE 8599, Solid State Lasers XXII: Technology and Devices, 859907 (6 March 2013); doi: 10.1117/12.2012519

Published in SPIE Proceedings Vol. 8599:
Solid State Lasers XXII: Technology and Devices
W. Andrew Clarkson; Ramesh Shori, Editor(s)