Abstract
We show that the propagation direction of the Dirac-cone modes of photonic-crystal slabs can be continuously controlled by the polarization of the incident wave. This property is realized by their isotropic dispersion relation and anisotropic mixture of two dipolar wave functions. To clarify these features, we formulate a Green-function method to describe the excitation process of the Dirac-cone modes and analyze the coupling strength with the incident wave by group theory. This angular dependence of the intensity distribution of the excited wave can be used for experimentally detecting the Dirac cones and distinguishing their mode symmetry.
- Received 1 July 2014
DOI:https://doi.org/10.1103/PhysRevA.90.013835
©2014 American Physical Society