FDTD simulations were performed using a commercially available solver software (AN-SYS/Lumerical) on a homemade workstation with Dual CPU (AMD EPYC 7302 16 core × 2), 512 GB (32 GB × 16) of DDR4 memory. To simulate metasurface response in a broad wavelength range from visible to mid-infrared (MIR) wavelengths, material permittivity data for Au, Cr and SiO 2 reported by Palik was employed . In this study, reflectance spectra simulations were performed using a plane wave source set to illuminate the MIM structures from the top nanodisk-patterned side, incident along z-axis. The reflection readout monitor was placed above the light source. The MIM structure was framed along the x-and y-directions using periodic boundary conditions, whereas a perfectly matched layer (PML) was used for termination along the the z-coordinate axis. Absorption and scattering cross-section simulations were conducted on same configuration of MIM structures, key difference being that a total-field scattered-field (TFSF) light source was initialized. Two sets of power monitors were placed inside and outside of the TFSF source volume, respectively for calculating the absorbed and scattered optical powers.