Optical transformation design of waveguide bends and splitter in photonic crystals

In this paper, an alternative approach for waveguide branch design in photonic crystals is presented. Two kinds of waveguide branches, including L-shaped waveguide bender and T-shaped splitter, are theoretically designed by using the method of transformation optics. Based on the parameters designed, electromagnetic simulations by finite-element method on detailed examples have been performed to validate the desirable properties of low reflection and minimized distortion at the branching region and to exhibit broadband for TE wave.