Article

S. NOUH, P. BALDI, M. DE MICHELI, G. MONNOM, D. B. OSTROWSKY, E. LALLIER, M. PAPUCHON
1994 Journal de Physique IV : Proceedings  
In this paper, we report the influence of proton exchange waveguide parameters on the fluorescence characteristic of Nd:LiTaOj . This information permitted the realization of a stable, C.W. Nd doped lithium tantalate waveguide laser. It presents a threshold of 24 mW and a slope efficiency of 15%. Operating at about 60°C, it was possible to observe up to 8 mW output power at 1.0816 pm for 75 mW absorbed pump power without any instabilities due to photorefractive effects, which are the best
more » ... are the best results observed to date. Following the recent success in fabricating waveguide lasers and laser devices in rare-earth doped lithium niobate 12,3, it appeared interesting to develop similar elements in rare-earth doped lithium tantalate in view of this latter material's reputation for having a considerably higher optical damage threshold. Unfortunately, first attempts, using Proton Exchanged (PE) waveguides on Nd:LiTa03 were not very successful4. In order to improve these performances we decided to use an annealed PE waveguide, which was realized on a X-cut lithium tantalate substrate5 doped with 0.1 mole % of ~d 3 + . A titanium mask consisting of 13 groups of 7 guides with opening widths ranging from 1 to 7 pm was used to fabricate the guides. Proton exchange was carried out for 3.5 hours, in a benzoic acid bath melted at 330°C and diluted with 0.5 mole % lithium benzoate. This results in a high proton density step index profile guide6, with protons having replaced Article published online by EDP Sciences and available at http://dx.
doi:10.1051/jp4:19944119 fatcat:us4dur3r7nfnlgubaua2sbewla