Wavelength-selective near unity absorber based on fabry-pérot nanoresonators

We proposed and analyzed a planar narrow-band absorber based on a bi-layer metal/dielectric structure. The planar absorber uses the Fabry-Pérot resonance and the inherent loss of the metals, for maximum light absorption in the range of the electromagnetic spectrum visible to the near infrared. The absorption resonance peak can be shifted to other regions of the spectrum by varying the dielectric film thicknesses. It is also possible to control the absorption with the angle of incidence for TE and TM polarization modes. The high absorption (near unity) and the high tolerance to fabrication errors of the proposed absorber can be explored in a large number of optoelectronic devices. © 2021 SBMO/SBMag