High Transmission through Sharp Bends in Photonic Crystal Waveguides

We demonstrate highly efficient transmission of light around sharp corners in photonic band-gap waveguides. Numerical simulations reveal complete transmission at certain frequencies, and very high transmission $(>95%)$ over wide frequency ranges. High transmission is observed even for 90\ifmmode^\circ\else\textdegree\fi{} bends with zero radius of curvature, with a maximum transmission of 98% as opposed to 30% for analogous conventional dielectric waveguides. We propose a simple one-dimensional scattering theory model with a dynamic frequency-dependent well depth to describe the transmission properties.