Tunable mid-infrared coherent perfect absorption in a graphene meta-surface

TL;DR

This paper demonstrates tunable mid-infrared coherent perfect absorption using graphene nanoribbon meta-surfaces, highlighting the potential for adjustable optical devices in detection and signal processing.

Contribution

It introduces a method to achieve and tune CPA in the mid-infrared using graphene meta-surfaces with strong resonances and phase control.

Findings

Existence of quasi-CPA frequencies in graphene meta-surfaces.

CPA can be significantly tuned via geometric and electrical modifications.

Experimental data supports the practical realization of CPA with graphene.

Abstract

We exploited graphene nanoribbons based meta-surface to realize coherent perfect absorption (CPA) in the mid-infrared regime. It was shown that quasi-CPA frequencies, at which CPA can be demonstrated with proper phase modulations, exist for the graphene meta-surface with strong resonant behaviors. The CPA can be tuned substantially by merging the geometric design of the meta-surface and the electrical tunability of graphene. Furthermore, we found that the graphene nanoribbon meta-surface based CPA is realizable with experimental graphene data. The findings of CPA with graphene meta-surface can be generalized for potential applications in optical detections and signal processing with two-dimensional optoelectronic materials.