Coaxial periodic optical waveguide

Guided modes in a dielectric waveguide structure with a coaxial periodic mu lti-layer are investigated by using a matrix formula with Bessel functions. We show that guided modes exist in the structure, and that the field is co nfined in the core which consists of the optically thinner medium. The disp ersion curves are discontinuous, so that the modes can exist only in partic ular wavelength bands corresponding to the stop bands of the periodic struc ture of the clad. It is possible that the waveguide structure can be applie d filters or optical fibers to reduce nonlinear effects. (C) 2000 Optical S ociety of America.