Two-Dimensional Photonic Crystal Couplers for Unidirectional Light Output

We propose the use of two-dimensional photonic crystal slabs to improve the directionality of output coupling from planar waveguides and distributed feedback lasers. We present a theory underlying the operation of such structures and design criteria for emission in desired directions. As an example, we demonstrate a vertical coupler integrated with an organic distributed feedback laser, use computer simulations to find its coupling constant and efficiency and then discuss its feasibility.