Goos–Hänchen shift in a one-dimensional dual-cavity photonic crystal containing graphene and Weyl semimetal

This paper investigates the Goos–Hänchen (GH) shift in a one-dimensional photonic crystal (1DPC) structure with a dual-cavity configuration. It consists of two photonic micro-cavities, with arrangement of ${\left(\text{AB}\right)}^{N}G{\left(\text{BA}\right)}^{M}BC{\left(\text{BA}\right)}^N$, one is designed with a Weyl semimetal (C) layer and the other one with a graphene (G), where A and B are dielectric layers. The reflection spectrum of an incident wave with TM polarization, its relative phase and the corresponding GH shift are calculated using the 2 × 2 transfer matrix method. The results indicate that the proposed structure exhibits two defect modes at a frequency of 235 THz (λ $=8.01\mu m$), occurring at angles of 18.7 and 53.9°, which lead to GH shifts of +37.8 λ and −4.9 λ, respectively. The effect of the G and C relative position, the chemical potential of graphene, the Fermi energy and the distance between Weyl nodes have examined for controlling the GH shift. This high tunability makes the proposed structure suitable for designing controllable optical devices and highly sensitive sensors based on the GH shift.