Two-dimensional photonic crystal cavity and channel add/drop filter

摘要

In 2D photonic crystals, cavities having a heightened Q factor are made available, wherein combining the high Q cavities with waveguides affords channel add/drop filters having high resolution. In a cavity constituted by a point defect within a 2D photonic crystal, the 2D photonic crystal is configured by an arrangement, in a two-dimensional lattice of points defined in a slab ( 1 ), of low-refractive-index substances ( 2 ) having a low refractive index relative to the slab ( 1 ) and being of identical dimension and shape. The point defect ( 4 ) contains a plurality of three or more lattice points that neighbor one another, and in these lattice points no low-refractive-index substances ( 2 ) are arranged; therein the dimension of the low-refractive-index substance ( 2 ) that should be arranged to correspond to at least one of the lattice points nearest the point defect ( 4 ) is dimensionally altered from a predetermined dimension.