Waveguide Bend of 90⁰ in Two-Dimensional Triangular Lattice Silicon Photonic Crystal Slabs

We design and realize a 90°waveguide bend in two-dimensional triangular lattice silicon photonic crystal slabs by connecting linear waveguides along the orthogonal Γ - K and Γ- M directions. A pass band of 70 nm is realized by optimizing the geometry of the Γ - M waveguide. The connection region of the waveguide bend is optimized to improve the transmission efficiency of infrared light through the two different kinds of waveguides. The transmission efficiency of an optimized single bend is about 75% in simulation and 45% in measurement.