Fast light propagating waveguide composed of heterogeneous metamaterials

A symmetrical three-layer fast light waveguide based on photonic crystal heterostructure is proposed in this article. Two types of photonic crystal where their effective optical parameters such as permittivity and permeability are variable from negative to positive at vicinity of the “Dirac-like” point frequency, are designed. Then the symmetrical three-layer light waveguide composed of these two different photonic crystals (heterogeneous structure at the junction between the cladding and the core) are constructed. By analyzing the anomalous dispersion mode of this waveguide, numerically calculated the group velocity to be negative. The light propagation effect of the waveguide is simulated, and it shows that the waveguide can confine light to the core layer well. In addition, observing the backward moving behavior of the wave packet by incident modulated gaussian pulses envelope, further verifying the generation of fast light. These numerical simulation results agree well the analytical analysis. The proposed waveguide structures in this article may improve the sensitivity of optical instruments and offer potential applications in the fields of integrated photonic circuits, on-chip optical interconnect, and fast optical communication and transmission.