In accordance with the present invention, one or more laser diodes are efficiently coupled into a waveguide amplifier in order to provide either an efficient amplifier or a laser. Light from one or more laser diodes is efficiently coupled into one or more waveguides through the effects in the refractive index between the core material of the waveguide and the cladding material around the waveguide. Both the core material and the cladding material can be deposited with a high degree of uniformity and control in order to obtain the coupling.