Low-loss, wide-angle Y splitter at ∼16-µm wavelengths built with a two-dimensional photonic crystal

Abstract
We report a successful experimental realization of a photonic-crystal Y splitter operating at λ1.6 µm. Our device has a large splitting angle of 120° and a miniature size of 3 µm×3 µm. Furthermore, the Y-splitter loss is measured to be 0.5–1 dB at λ=16401680 nm, making the Y splitter promising for integrated photonic-circuit applications. These unique properties are attributed to the new guiding principle made possible by the photonic bandgap.