Talbot Effect at the Dirac-Like Cone in Kagome Lattice Microwave Photonic Crystal

A Talbot effect is observed in a Kagome lattice photonic crystal (KPC) at the Dirac-like cone. The Dirac-like cone and Dirac-like point are achieved at the center of the Brillouin zone (BZ) with triply degenerate bands with two linear bands and one flat band intersecting the cone at the same frequency. Using band-structure calculations, it is shown that the Dirac-like cone is formed in a relatively high-frequency region and composed of interchangeable but opposite cones which are formed by two linear dispersion curves of the KPC in the vicinity of the Dirac-like point. Near the point of degeneracy, in addition to Talbot effect, unique wave propagation phenomena such as defect-insensitive propagation characteristics and cloaking of objects are observed.