Mode Analysis and Design of a Low-Loss Photonic Crystal 60 degrees Waveguide Bend

The guided modes of a two-dimensional photonic crystal straight waveguide and a waveguide bend are studied in order to find the high transmission mechanism for the waveguide bend. We find that high transmission occurs when the mode patterns and wave numbers match, while the single-mode condition in the waveguide bend is not necessarily required. According to the mechanism, a simply modified bend structure with broad high transmission band is proposed. The bandwidth is significantly increased from 19 to 116 nm with transmission above 90%, and covers the entire C band of optical communication.

National Nature Science Foundation of China 10634080 60677046Chinese National Key Basic Research Special Fund 2006CB921700 National High Technology Research and Development Program of China 2006AA03Z403 This work was supported by the State Key Program, of National Nature Science Foundation of China under Grant 10634080, the National Natural Science Foundation of China under Grant 60677046, the Chinese National Key Basic Research Special Fund under Grant 2006CB921700, and the National High Technology Research and Development Program of China under Grant 2006AA03Z403.