Strong Group Delay Dispersion in 3D Photonic Band Gap Crystals and Planar Microcavities

It is well-known that nanophotonic structures give rise to intricate dispersion relations that strongly differ from those in homogeneous media, for instance, the appearance of band structures [1]. Such band structures reveal forbidden gaps where wave vectors become complex and the slope - the group velocity - is strongly modified to reveal slow light [3], [4], and a strong alteration of the group velocity dispersion, also known as chirp in optics and effective mass in solid state physics. Control thereof is crucial for applications (in comms and telecom) and for fundamental reasons namely as an alternative probe to local density of states and localization.