Abstract

As a promising candidate for the next generation communication and information systems, photonic crystals (PCs) have received intensive research interests in the past few years. To explore the advanced functionalities of PCs, three-dimensional (3D) structures with a complete bandgap are crucial. To this end, materials of high refractive index contrast have to be employed to fabricate 3D PCs. Several approaches have been proposed to form 3D PCs in high index materials, for example using semiconductor lithography, generating inverse structures in self-assembled opal lattices and direct writing in chalcogenide glasses. Semiconductor lithography has been proved to be an efficient and precise way to fabricate two-dimensional (2D) PCs, but for 3D structures, this method is too expensive, complicated and time-consuming. A complete bandgap has been demonstrated in titanium inverse opal structures only for a limited geometry, thus lacking of designing flexibility. Direct laser writing in high index chalcogenide glasses on the other hand involves a complicated aberration problem when the fabrication depth increases, leading to 3D structures of insufficient periodicities.

© 2007 IEEE