Gallium-diffused ridge waveguides in sapphire

Summary form only given. It has been shown that Ga:sapphire channel waveguides with small mode sizes may be realized by diffusion and ion-beam milling. Co-doping of sapphire with titanium and gallium is expected to lead to waveguide lasers with improved performance, as the gallium-diffused waveguide yields a small mode size for low pump power threshold and the titanium concentration may be flexibly adjusted for optimum laser operation. The realization of a passive waveguide technology in sapphire is also expected to allow the integration of passive devices for wavelength selection and tuning gain sections locally doped with titanium.