Electrically tunable Bragg gratings in single-mode polymer optical fiber.

We present what is to our knowledge the first demonstration of a tunable fiber Bragg grating device in polymer optical fiber that utilizes a thin-film resistive heater deposited on the surface of the fiber. The polymer fiber was coated via photochemical deposition of a Pd/Cu metallic layer with a procedure induced by vacuum-ultraviolet radiation at room temperature. The resulting device, when wavelength tuned via joule heating, underwent a wavelength shift of 2 nm for a moderate input power of 160 mW, a wavelength to input power coefficient of -13.4 pm/mW, and a time constant of 1.7 s(-1).

Characterization of surface-plasmon modes in metal-clad optical waveguides.

Finite-element analysis, based on the vector H-field formulation and incorporating the perturbation technique, is used to calculate the complex propagation characteristics of metal-coated dielectric waveguides. The propagation and attenuation characteristics of the surface-plasmon modes at the metal/dielectric interfaces are presented. The effects on the optical properties of metal-clad optical fibers with infinite and finite cladding thickness and the formation of the supermodes due to the coupling between the surface-plasmon modes in the presence of different surrounding materials are also investigated.

Finite-Element Analysis of Lossy TE-TM modes in Metal-Clad Optical Waveguides.

Finite-element analysis employing the scalar and vector H-field formulations and with the aid of the perturbation technique is used to calculate the TE-TM complex propagation characteristics of integrated optical devices in gallium arsenide, lithium niobate, and silica fiber, incorporating a lossy metal cladding. The propagation and attenuation properties of several types of metal-clad planar optical waveguide, which exhibit surface-plasmon properties for the TM polarization, are reviewed, and the modal loss caused by the metal cladding in a titanium-diffused lithium niobate electro-optic directional coupler modulator, an indium gallium arsenide phosphide-based TE-TM optical polarizer, and a submicron metal-clad silica fiber suitable for near-field optical scanning microscopy is calculated.

Finite-element analysis of surface-plasmon modes for lossy optical waveguides by the use of perturbation techniques.

A finite-element analysis, with the aid of perturbation techniques, is used to determine the complex propagation characteristics of surface-plasmon modes that are supported by metal-dielectric interfaces. Symmetrical and nonsymmetrical three-layer optical waveguides incorporating a thin metal layer are studied, and the variations of the effective index and the attenuation constant with metal thicknesses are presented for both the short-range and long-range modes. Results are compared with previously published research, which was based on alternative approaches. Furthermore, for the first time to our knowledge, the complex propagation characteristics are presented for a coupled structure incorporating a surface-plasmon region with two-dimensional confinement.