Dual dielectric grating-assisted enhancement of Goos-Hänchen shift in monolayer graphene

Abstract

Recently, the dielectric gratings have been used in enhancing the Goos-Hänchen (GH) shifts of monolayer graphene. However, many of these structures are limited within single dielectric grating. Dual dielectric gratings are compelling candidates for the manipulation of the light-matter interaction owing to their flexible degree of freedom in geometrical parameters. Here, we present the GH shift of the reflected wave in the dual dielectric grating layers by using rigorous coupled-wave analysis (RCWA) and stationary phase method, where a monolayer graphene is placed on top of the lower dielectric grating layer and the upper and lower dielectric grating layers have different filling factors. It is found that a relatively large GH shift, with amplitude up to more than 8000 times of the incident wavelength, can be achieved in the dual dielectric grating layers with monolayer graphene due to the joint excitation of the guided mode resonance (GMR) in both the upper and lower dielectric grating layers. In addition, we can control the magnitude and position of GH shifts by changing chemical potential of monolayer graphene and the geometrical parameters of the dual dielectric grating layers. Our work opens a possibility for the improvement of the GH shift in the combined structure with the dual dielectric grating layers and the two-dimensional layered structure, which might enable the novel optoelectronic devices.

Giant goos–hanchen shift with heigh reflection base on guided mode resonance in trapezoidal hBN/dielectric metasurface

“…Therefore, some simulations are based on a plane wave. Ma et al presented the GH shift of reflected wave in the dual dielectric grating layer, with the GH shift being more than 8000 times the incident wavelength, and the reflection of only 0.0022 [20]. Zhu et al demonstrated that the asymmetric grating with monolayer MoS 2 had achieved a GH shift as high as 9490λ, with a reflection of only 0.018 [21].…”