Barth, C.; Burger, S.; Becker, C.: Symmetry-dependency of anticrossing phenomena in slab-type photonic crystals. Optics Express 24 (2016), p. 10931/1-8
Open Accesn Version

The optical properties of photonic crystals (PhCs) are strongly affected by their spatial symmetry characteristics. We observe anticrossing phenomena for large-area slab-type silicon PhCs sandwiched between a glass substrate and air. If a glass superstrate plus an index-matching fluid is added, thus establishing a mirror symmetry in z-direction, the anticrossing disappears. These characteristics are analyzed numerically using a finite-element Maxwell solver, and experimentally using large area samples made by nanoimprint lithography. We further discuss the findings by symmetry considerations.