A germanium inverse woodpile structure with a large photonic band gap

A germanium inverse woodpile structure exhibiting a 25% wide photonic band gap (PBG) is created by direct-write assembly of a polymeric template (see figure and cover) followed by sequential deposition of a sacrificial oxide bilayer and germanium. Upon removal of the template and sacrificial layers. the reflectance spectrum shows a large peak in the mid-IR rep-ion, indicative of a PBG considerably larger than those shown by conventional woodpile structures.