Slow light in narrow-core hollow optical waveguide with low loss and large bandwidth

Abstract

A narrow-core hollow waveguide with low loss is proposed that exhibits slow light characteristics. The slow light is guided in air between the top and bottom mirrors, each based on high-index-contrast gratings. The proposed design shows a low propagation loss of 1.8 dB/cm at a 1-μm-thick narrow air core, and the loss remains low for a broad range of wavelengths from 1200 to 1600 nm. Also, the flat band slow light is realized at a grating period of 0.8 μm in 1-μm-thick narrow air core. Further design analysis reveals a large fabrication tolerance of the proposed hollow structure with respect to the grating period. © 2016 Optical Society of America.