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
... 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.