A semi-Dirac point and an electromagnetic topological transition in a dielectric photonic crystal.

  • Ying Wu
  • Published 2014 in Optics express

Abstract

Accidental degeneracy in a photonic crystal consisting of a square array of elliptical dielectric cylinders leads to both a semi-Dirac point at the center of the Brillouin zone and an electromagnetic topological transition (ETT). A perturbation method is deduced to affirm the peculiar linear-parabolic dispersion near the semi-Dirac point. An effective medium theory is developed to explain the simultaneous semi-Dirac point and ETT and to show that the photonic crystal is either a zero-refractive-index material or an epsilon-near-zero material at the semi-Dirac point. Drastic changes in the wave manipulation properties at the semi-Dirac point, resulting from ETT, are described.

DOI: 10.1364/OE.22.001906

Cite this paper

@article{Wu2014ASP, title={A semi-Dirac point and an electromagnetic topological transition in a dielectric photonic crystal.}, author={Ying Wu}, journal={Optics express}, year={2014}, volume={22 2}, pages={1906-17} }