Abstract: A transverse Bragg resonance waveguide is comprised of a waveguiding channel, and on at least two opposing sides of the channel two periodic index media; and a means for providing gain in the periodic index media. In one embodiment the waveguiding channel is planar and is sandwiched on two opposing sides by the periodic index media. In another embodiment the waveguiding channel is cylindrical and is surrounded by the periodic index media. The means for providing gain in the periodic index media is electrical or optical pumping. The periodic index media comprises a periodic lattice of regions having an index of refraction distinct from the channel, such as an array of transverse holes defined in a planar semiconductor substrate in which the channel is also defined, or an array of longitudinal holes defined in a cylindrical semiconductor fiber in which the channel is also longitudinally defined.

Abstract: Composite films of multicomponent materials, such as oxides and nitrides, e.g., lead zirconate titanate, are deposited by dc magnetron sputtering, employing a rotating substrate holder, which rotates relative to a plurality of targets, one target for each metal element of the multicomponent material. The sputtering is carried out in a reactive atmosphere. The substrates on which the layers are deposited are at ambient temperature. Following deposition of the composite film, the film is heated to a temperature sufficient to initiate a solid state reaction and form the final product, which is substantially single phase and substantially homogeneous.