Pulsed laser deposition produces thin-film Nd:GGG waveguide laser
A crystalline neodymium-doped gadolinium gallium garnet (Nd:GGG) planar waveguide lased at several wavelengths centered around 1.062 ?m when pumped by a Ti:sapphire laser at
808 nm in experiments at the University of Southampton (Southampton, England). The thin-film waveguide structure was grown by pulsed laser deposition (PLD) on a single-crystal YAG substrate. University researchers believe this is the first reported operation of a waveguide laser fabricated using PLD. Waveguide lasers are of interest because the large-intensity-length
product and good pum¥laser and signal mode overla¥that are possible with the waveguide geometry can mean a lower pump-laser power threshold as compared to bulk lasers.
Previously, ion implantation, liquid-phase epitaxy, and metal-organic chemical-vapor deposition have been used for growing planar and channel waveguides. Ion implantation is
relatively expensive, however, and the other two techniques lack versatility. According to the researchers, PLD is a fast and versatile alternative and can grow high-quality single-crystal layers of the correct composition. In future experiments the researchers expect to reduce the pump-power threshold of the waveguide laser by etching the films to produce channel waveguides.