WAVE-GUIDES AND WAVE-GUIDE LASERS FABRICATED BY ION-IMPLANTATION

Ion implantation has now become established for the fabrication of waveguides on the surfaces of insulating crystals and glasses. The physical effects of energetic light ions (e.g., MeV He+) may be used to change the refractive index and-thereby define a waveguide profile in a bulk laser material. Alternatively, direct active dopant implantation may be used to define the lasing and/or guiding region of a device. The first method has now been used to produce waveguide lasers in several materials giving threshold absorbed powers as low as 500 muW and slope efficiencies of approximately 30%. The second method has been used to produce good waveguides but it has not yet succeeded in producing a laser. Progress has been made, however, in understanding the mechanisms involved in Er implant doping. Future developments are discussed for laser production and their wavelength conversion to visible radiation.