Independently tunable infrared absorber using stacked molybdenum disulfide metasurfaces.

[Display omitted] • The proposed device constitutes an infrared tri-band perfect absorber. • Absorption peaks can be independently tuned by varying the carrier density of MoS 2. • Multilayered interference model is proposed to elucidate the absorption mechanism. • The absorber is rather insensitive to light polarization and angle of incidence. In this paper, we present an independently tunable infrared tri-band perfect absorber, which consists of double-layer stacked molybdenum disulfide (MoS 2) metasurfaces and a gold mirror separated by insulating layers. The light absorption in monolayer MoS 2 is strongly enhanced, and three absorption peaks of over 99.5% are achieved. We demonstrate that the three absorption peaks can be independently tuned by changing the carrier density of the corresponding MoS 2 layer, indicating no interlayer coupling between the top and bottom MoS 2 layers. Based on this, we propose a multilayered multiple interference model to elucidate the independently tunable perfect absorption mechanism. The theoretically calculated absorption spectrum agrees excellently with the simulated spectrum. In addition, the tri-band perfect absorber possesses polarization-independent and incident-angle-insensitive properties. The proposed metasurfaces may help in designing multilayered metasurface absorbers and thus the fabrication of MoS 2 -based optoelectronic devices such as modulators, tunable sensors, thermal emitters, and photodetectors for infrared waves. [ABSTRACT FROM AUTHOR]