Optical amplification and photosensitivity in sol-gel based waveguides

The sol-gel process has emerged as an effective route for the fabrication o f optical waveguides and guided wave devices and circuits. In particular, i t is possible to incorporate active dopants like neodymium, erbium, and ces ium for integrated optical active devices and circuits. In this paper, a re view of recent research on active devices and circuits based on sol-gel pro cess is made. Specific studies undertaken in our laboratory on optical ampl ification and photosensitivity characteristics of sol-gel optical films are presented. In the case of modeling and analysis of active sol-gel films fo r the study of optical amplifiers, we present the Atomic Susceptibility The ory of lasers and also the method of rate equations, duly taking into accou nt the waveguide parameters. The Beam Propagation Method is applied to stud y the propagation and gain characteristics of actively doped sol-gel film d evices such as straight waveguide, Y-branch, and directional coupler. Forma tion of Bragg gratings in cerium-doped films are investigated. Also, futuri stic applications in MEMS where the sol-gel process will be effectively use d to form optical layers that can be controlled by mechanical effects are p ointed out.