Sharply bent hollow optical waveguides formed by an omni-directional reflector

In this work, we demonstrate theoretically and experimentally the air core bent optical waveguide composed of omni-directional reflectors on a silicon substrate. Amorphous silicon and silicon oxide are used for high index-contrast Bragg reflectors. The transmission efficiency of power for the bent optical waveguide with various bending angles of 1°-90° is calculated by the two-dimensional finite-difference time-domain method and the three-dimensional beam propagation method. The sample is measured using the end-butt method. The device exhibits a lower polarization dependent loss at the operation wavelength of 1550 nm.