Modeling and Fabrication of Hollow Optical Waveguide for Photonic Integrated Circuits

Abstract

We present the design and fabrication of hollow optical waveguides with highly reflective mirrors on the guiding walls of waveguides. We demonstrate the possibility of polarization-insensitive and low-loss slab waveguides by loading properly designed dielectric multilayer mirrors. We also propose a novel three-dimensional (3D) hollow waveguide with an etched groove structure for confining light in a lateral direction. We also predict that the propagation constant is independent of the ambient temperature, resulting in temperature-insensitive photonic waveguide devices such as optical filters and grating optical demultiplexers. We fabricate slab and 3D hollow optical waveguides with Au coating and present their propagation characteristics. The propagation loss of a slab waveguide was 1–2 dB/cm and 3–4 dB/cm for transverse electric (TE) and transverse magnetic (TM) modes, respectively. We also suggest the possibility of low-loss 3D hollow waveguides.