Gapless unidirectional photonic transport using all-dielectric kagome lattices

Abstract

This paper shows that kagome lattices can be used for broadband and efficient unidirectional photonic edge mode propagation at sharp 120 degree bending. The authors propose a realistic device composed of an InGaAsP free-standing photonic crystal working at telecommunication wavelengths and further show that it has negligible vertical losses. Compared to conventional photonic topological insulator designs, the simplicity of the kagome-lattice-based device and its all-dielectric nature make it possible to fabricate it using many conventional techniques.