We describe the fabrication and evaluation of a low-loss, high-Δ optical waveguide consisting of heterostructured photonic crystals. The waveguide is composed of a multilayer stack of Ta<sub>2</sub>O<sub>5</sub>/SiO<sub>2</sub> and is prepared by use of the autocloning technique. Light is guided in the waveguide by the difference in the effective refractive indices of the constituent photonic crystals. By improving the design of the core region so that is has a flat multilayer structure, we achieve Δ=3.0% for the in-plane direction and net propagation loss of 0.56dB/mm at λ=1.6μm . Experiments also suggest that the bending loss of the waveguide can be reduced to less than 0.1 dB if the curvature radius is larger than 700μm .
© 2003 Optical Society of America
(230.3120) Optical devices : Integrated optics devices
(230.4170) Optical devices : Multilayers
(230.7380) Optical devices : Waveguides, channeled
(230.7390) Optical devices : Waveguides, planar
(310.1860) Thin films : Deposition and fabrication
K. Miura, Y. Ohtera, H. Ohkubo, N. Akutsu, and S. Kawakami, "Reduction of propagation and bending losses of heterostructured photonic crystal waveguides by use of a high-Δ structure," Opt. Lett. 28, 734-736 (2003)