Tunable ultra-high-efficiency light absorption of monolayer graphene using critical coupling with guided resonance.

We numerically demonstrate a novel monolayer graphene-based perfect absorption multi-layer photonic structure by the mechanism of critical coupling with guided resonance, in which the absorption of graphene can significantly reach 99% at telecommunication wavelengths. The highly efficient absorption and spectral selectivity can be obtained with designing structural parameters in the near-infrared region. Compared to previous works, we achieve the complete absorption of single-atomic-layer graphene in the perfect absorber with a lossless dielectric Bragg mirror, which not only opens up new methods of enhancing the light-graphene interaction, but also makes for practical applications in high-performance optoelectronic devices, such as modulators and sensors.