Topological properties of bulk and edge states in honeycomb lattice photonic crystals: the case of TE polarization.

Topological properties of bulk and edge states in honeycomb lattice photonic crystals are investigated theoretically for transverse-electric (TE) polarization. Breaking of space-inversion and time-reversal symmetries is considered at optical frequencies. The bulk band structure exhibits a topological phase transition by changing the degree of the broken symmetries. The resulting phase diagram correlates with zigzag and armchair edge states, and the so-called bulk-edge correspondence is verified. The effects of flat interfaces near the edges are also discussed.