S.J. Field

Growth and low-threshold laser oscillation of an epitaxially grown Nd:YAG waveguide

We report 1.064-microm laser operation of an epitaxially grown Nd: YAG planar waveguide with thresholds as low as ~0.7 mW when high-reflectivity mirrors are used. The output is single mode and, when a 83% reflectivity output coupler is used, has a diode pumped slope efficiency of ~40%. Output powers in excess of 60 mW have been obtained when pumping with a Rhodamine 6G dye laser.

Ion-implanted Nd:MgO:LiNbO3 planar waveguide laser

Laser oscillation in an ion-implanted planar Nd:MgO:LiNbO(3) waveguide is demonstrated for the first time to our knowledge. Details of the waveguide structure, spectroscopic properties, photorefractive effects, and laser performance are given. A simple calculation of the absorbed power threshold gives ~8 mW, in fair agreement with the experimental value of ~17 mW.

Ion-implanted Nd:GGG channel waveguide laser

We report what is to our knowledge the first fabrication and laser operation of ion-implanted Nd:GGG channel waveguides. Diode-pumped operation has been achieved with absorbed power thresholds as low as ~2 mW and a slope efficiency of ~30% with respect to absorbed power.

Characterization of ion implanted waveguides in Nd:YAG

Ion implantation into Nd:YAG has been used to produce waveguides which are capable of supporting laser action. The refractive index profiles have been characterized as a function of ion dose and energy, implant temperature, and subsequent thermal annealing. Transmission losses down to 1.2 dB/cm have been obtained in the optimized waveguides. There is a temperature independent index enhancement of ∼0.15% in the electronic stopping (guiding) region. The nuclear collision damage is temperature dependent, and shows an initial index increase (∼0.3% for dose 1 × 1016 ions/cm2), but a subsequent decrease of up to several percent, which forms an optical barrier, as has been observed in many other crystalline materials. The best mode confinement and attenuation is obtained by utilizing the low dose nuclear index enhancement produced by several equally spaced implants (multiple energy) to give a broad well with Δn∼0.25%. Several unusual features of the profiles are reported and discussed.

An efficient, diode-pumped, ion-implanted Nd: GGG planar waveguide laser

We report the first laser operation of an ion-implanted Nd:GGG planar waveguide laser at 1.062µm. Diode array and dye-laser pumping is described with threshold absorbed powers as low as 8mW. Slope efficiencies of 30% with respect to absorbed power have been observed with output powers of up to 40mW.

Optically written waveguides in ion implanted Bi4Ge3O12

We report the first observation of optically written channel waveguides in ion implanted Bi4Ge3O12 (BGO). Raman spectroscopy has been used to investigate the changes occurring due to both the original ion implantation and the subsequent optical writing of channel waveguides

Diode Pumped, Garnet Channel Waveguide Lasers

Ion implantation is a technique which can be used to form waveguides in a wide range of materials - including crystals of the garnet family for which no alternative techniques exist - by bombarding the material surface with high energy ions and altering the refractive index [1]. We report the use of this method to form channel waveguides in two Nd3+ doped materials; Nd:YAG and Nd:GGG both of which have operated as ion implanted planar waveguide lasers [2,3]. The additional confinement in the plane is achieved without any significant increase in propagation losses, which are comparable in the planar and channel guides. In the Nd:YAG system submilliwatt thresholds were observed.

Efficient, Low-Threshold Ion-Implanted Channel Waveguide Lasers

He+ Ion implantation has been used to create channel waveguides in Nd doped YAG and GGG. Low threshold, efficient, diode-pumped laser performance is reported.