A wide-angle broadband polarization-dependent absorber with stacked metal-dielectric grating

• We propose a broadband absorber using stacked metal-dielectric grating with fixed width of structured layers.
• The simulation results show that the minimal absorption magnitude is larger than 0.8 in the broadband range for angles up to 60°.
• Furthermore, such broadband absorption can be tuned by shrinking or enlarging the grating parameters.
• This broadband absorber is a good candidate for potential applications such as detectors and phase imaging.

We report an absorber in the mid-infrared regime by using stacked metal-dielectric grating structure. The simulation results show that the minimal absorption magnitude is larger than 0.8 in the broadband range for angles up to 60° for TM polarization (magnetic field is parallel to grating grooves). At the same time, absorption for TE polarization (electric field is parallel to grating grooves) is negligible. Furthermore, such broadband absorption for TM polarization can be tuned by shrinking or enlarging the grating parameters. This absorber is a good candidate for potential applications such as polarization detectors and polarizers.